Virology

Virology Part-1

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  • DPT
    • Preservative Thiomersal
      • (preserved in thee, give to mersal)
    • Adjuvant Aluminium hydroxide

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2 - scar
1- measles
3 - germen measles
4 - D - Dukes
5 - Erythema infectiosum
6 - roses
 
Virus
Receptors
CMV
Integrins
(heparan sulfate)
Integrate with CM
Parvovirus B19
P antigen on RBCs
Rabies
Nicotinic AChR
Rhinovirus &
Falciform Malaria
ICAM-1
I went with a Camera (ICAM) and shoot False (Falciform M) Rhino () (Human in Rhino attire)
SARS-CoV-2
ACE2
Measles
CD150 and PVRL4.
PVR() il 150() rs nu CD() itt kanum
EBV/ HHV 4
CD21
HHV 6
CD46 on T cells
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Tetanus
Tetanus
Rabies
Rabies
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Structure of a Virus

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  • Outer layer:
    • Envelope + envelope protein
    • Projections = Peplomers
  • Central part:
    • Capsid + viral genome (nucleic acid) = Nucleocapsid
  • Viral tegument:
    • Between envelope and nucleocapsid
  • Envelope sensitivity: Ether, Alcohol, Bile salt
  • Envelope labile to: Heat
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Non-enveloped Viruses

  • Enveloped DNA viruses
    • Mnemonic: PAP
      • Parvovirus
      • Adenovirus
      • Papovavirus
  • Enveloped RNA viruses
    • Mnemonic: PARCH
      • Picornavirus
      • Astrovirus
      • Reovirus
      • Calicivirus
      • Hepatitis A
      • Hepatitis E
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Genome Symmetry

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  • DNA viruses: Icosahedral symmetry (except Pox virus)
  • RNA viruses: Helical symmetry
  • Poxvirus: Complex symmetry
    • Pox → Complox

RNA Helical symmetry viruses

  • Mnemonic: He is MR FABulous
    • M: Myxovirus
    • R: Rhabdovirus
    • F: Filovirus
    • A: Arenavirus
    • B: Bunyavirus

Classification of Viruses

DNA viruses – Mnemonic: HAPPy

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  • Hepadnaviridae HBV
  • Herpesviridae HSV, HZV, EBV, CMV, HHV
  • Adenoviridae Adenovirus
  • Poxviridae Smallpox, Cowpox (Variola, Vaccinia, Molluscum)
    • Not chickenpox
  • Papovaviridae HPV, BL, JC, Polyoma, SV40
  • Parvoviridae Parvovirus
  • Bacteriophage
    • DNA virus
    • Tadpole-shaped
    • Role in transduction

RNA virus families

  • Picornaviridae
  • Paramyxoviridae
  • Caliciviridae
  • Togaviridae
  • Orthomyxoviridae
  • Bunyaviridae
  • Flaviviridae
  • Arenaviridae
  • Coronaviridae
  • Reoviridae
  • Rhabdoviridae
  • Retroviridae
  • Filoviridae

Size of Viruses

  • Largest: Poxvirus 300 nm
  • Smallest: Parvovirus 20 nm

Genome Size

  • Largest genome: Retrovirus
  • Smallest genome: Hepatitis D > Hepatitis B

Shape and Structure

Virus
Shape
Pox
Box
Pox → Box → Heavy → bcz dumbell inside it (dumb bell DNA core)
Rotavirus
Wheel-shaped
→ diarrhoea in children
Rota → Rotating wheel (wheel shaped) for children ()
Adenovirus
Space vehicle
Adeno → alien spaceship
Astrovirus
Star-shaped
Astrovirus → A star (Star shaped)
Rabies virus
Bullet
Ebola
Filamentous
Ebola → A bowl of sphagetti
Corona
Crown/Petal-like peplomers
Tobacco mosaic virus
Rod/Cigarette-shaped
tobacco mosaic → cigarrette / rod shaped
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DNA Virus – Rules and Exceptions

  • All DNA viruses = dsDNA
  • Exception → Parvovirus
    • ssDNA
    • Smallest (20 nm)
    • Causes slapped cheek appearance (5th disease → Erythema infectiosum)
    • Pavam → smallest → left alone (ssDNA) → got slapped ()
  • Circular Nucleic Acid:
    • HBV: Partially ds
    • HPV: Completely ds

RNA Virus – Rules and Exceptions

  • All RNA viruses = 1 copy of unsegmented ssRNA
  • Exceptions:
    • Retrovirus 2 copies
      • Re → 2
    • Reo/RotavirusdsRNA
      • Diarrhea → Double stranded → Rota hua bacha
Segmented viruses
BIRA or BORA
No of Segements
Bunyavirus
3
B ⇒ 3
Influenza (Orthomyxoviridae)
8
I → E → Eight
Reovirus/Rotavirus
11
R R → 11
Arenavirus
2
aRe → 2

Virus Cultivation

1. Animal Inoculation

  • Animal Inoculation into suckling mice brains
Virus
Paralysis in Mice
Serotypes
Diseases
Coxsackie A
Flaccid paralysis

A → Arms (LMN)
1 - 24
Hand-foot-mouth disease
Herpangina
Acute Hemorrhagic Conjunctivitis ()
↳ (
Coxsackie A24, enterovirus 70)
Coxsackie B
Spastic paralysis

B → Brain (UMN)
1 - 6
Hand-foot-mouth disease
Bornholm’s disease
(
Devil’s grip / Pleurodynia / Epidemic myalgia)
Carditis

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2. Embryonated Egg (4 cavities)

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Culture
Virus
Mnemonic
Chorioallantoic membrane
Vaccinia, Variola
HSV1, HSV2
CAMera → Very Very Hot Hot
Yolk sac
Chlamydia,
Arbovirus,
Rickettsia
CAR
Amniotic membrane
Influenza isolation
Inside amnion
Allantoic cavity
Yellow fever,
Influenza vaccine,
Rabies vaccine
Allan → Yellow Influenzer got rabies
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3. Cell Lines

Cell Lines
Divisions
Notes
Primary cell lines
5–10 divisions
Rhesus kidney cell line
Human amniotic cell line
Chick embryo fibroblast
Primitive like Monkey (Rhesus), Chick embyo, Amnion
Secondary cell lines
10–50 division
Human fibroblast-related
↳ Used for
CMV
WI38, MRC5
Human + Men (M) + Women (W)
Continuous cell lines
Immortal
HeLa, HEP-2, KB, McCoy,
Vero, Detroit 6, BHK, Chang C/I/L/K
Rest

Inclusion bodies

Inclusion bodies
Seen in
Paschen bodies
Variola (smallpox).
Pasha Vaari
Guarnieri bodies
Vaccinia
vaGGinia
Bollinger bodies
Fowl pox
Ball → Foul

Intracytoplasmic Inclusion Bodies:

  • Henderson Patterson bodies.
    • Positive for: Phloxine tartrate stain.
    • Molluscum contagiosum
      • Present with: Umbilicated lesions.
      • When pressed: Curdy material is extruded.
      • Microscopy: Cup-shaped structure.
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  • Halberstadter Prowazeki bodies:
    • Trachoma
    • Mnemonic: Trackil odan Horse Power venam
  • Levinthal Cole Lillie body:
    • C. Psittaci
    • Mnemonic: Levinthikkole Lillye sit aaki
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  • Negri Body:
    • Intracytoplasmic eosinophilic inclusion body
      • Seen in: Rabies.
    • Sellers stain
    • Seen after death
    • First siteAMMON horn of hippocampus
      • Rabies - Hippoptamus
      • Sell (Sellers) Nigro (Negri)
    • Second siteCerebellum
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Intranuclear Inclusion Bodies:

  • Cowdry type A
    • Seen in:
      • Yellow fever: Torres bodies.
      • Herpes Simplex: Lipschultz.
    • Mnemonic: Tore Yellow shirt → Kiss Her Lips
      • Cowdry Type A
        Cowdry Type A
  • Cowdry type B
    • Seen in:
      • Adenovirus.
      • Poliovirus.
    • Mnemonic: Adipoli breast

Both intracytoplasmic + intranuclear forms:

  • CMV (Cytomegalovirus)
    • Shows: Owl eye appearance.
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  • Measles
    • Shows: Warthin Finkeldey giant cells.
      • large grapelike clusters
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DNA Virus Families

Molluscum Contagiosum

Caused by Molluscum Virus (MCV), also called Molluscipox Virus

  • From the family of Poxviruses
    • Largest known DNA viruses
  • MCV1 and MCV2 cause molluscum contagiosum
  • It is contagious
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Presentation:

  • Usually in children
  • On the face or other body parts
  • May be positive family history
  • Lesions are:
    • Asymptomatic papules
    • Have an umbilicated centre
      • Indentation in the centre
      • May exude curdy/cheesy material when pressed.
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Pseudokoebner's Phenomenon:

  • Along the line of trauma
    • Autoinoculation of virus
  • Molluscum lesions seen along lines of trauma
  • Seen in warts and molluscum
  • Mnemonic:
    • Rub her hand → suddenly lesions came → said “What Mollu”

Histopathology:

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HP bodies
HP bodies
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  • Microscopic:
    • Cup-shaped lesion.
    • Henderson-Patterson (HP) bodies (pinkish).
  • Special Stain: 
    • Lendrum’s Phloxine Tartrate stain (for HP bodies).
  • Mnemonic: Frock (Flock) with cup () and showing umbilicus () → makes Happy (HP)
  • Intracytoplasmic eosinophilic inclusion bodies seen
    • Called Henderson-Paterson bodies or HP bodies
    • Viral bodies inside keratinocytes
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Treatment:

  • Usually self-limiting condition (if few lesions in a child)
  • If increasing, treatment is required
  • No oral medicine kills viruses
    • Oral medicines act as immunomodulators
  • In HIV-positive patients or severe disease
    • Levamisole
    • Cimetidine

Most common mode of treatment is destroying the virus

  • Chemically using:
    • 10% KOH
    • Trichloroacetic acid
  • Physically using:
    • Electrocautery
    • Radiofrequency
    • Laser
    • Cryotherapy

Mnemonic:

  • Mollu Thottal (Tricholoacetic acid) Pottunna (KOH) Prayama
  • Molle Lavan (Levamisole) Cinimakk (Cimetidine) kond poyapo HIV vannu

Other Poxvirus Infections (Zoonotic in Nature)

Ecthyma contagiosum:

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  • Parapox or Orf Virus:
    • Transmitted through sheep
    • Seen in people who handle livestock
  • Mnemonic: Ork (orf) vann sheep () ne para (parapox) vach easy (ecthymo) ayi kadichapo ingana paadu vann → contagious ayi

Milker's Nodule:

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  • Caused by Pseudopox Virus
  • Caused in patients handling cow
  • Manifestation (both):
    • Usually on exposed parts (e.g., hands)
    • Start with a necrotic area in the centre
    • Little oedema around it
    • Erythema around it
  • Mnemonic:
    • Maid milking (Milkers nodule) a cow (handling cow) → wearing exposing dress (exposed areas)
    • She is pseudo (psuedopox) → dont trust her
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Herpesviridae

Herpesviridae
Names
HHV1
Herpes simplex 1
Herpes
HHV2
Herpes simplex 2
Herpes
HHV3
Human Herpes Zoster Virus
↳ Causes
Chickenpox + Shingles
HHV4
Epstein–Barr virus
IMN
NPC
HHV5
Cytomegalovirus (largest)
IMN Like syndrome
HHV6 / 7
Human Herpesvirus 6
Roseola infantum
Pityriasis Rosea
HHV8
Human Herpesvirus 8
Kaposi sarcoma
PEL
Castleman’s disease

Herpes Simplex Virus (HSV-1 & HSV-2)

Virus

  • Linear dsDNA
  • HSV replication
    • Occurs in the nucleus
    • Linear dsDNA becomes circular inside host cell
    • Replicates by rolling circle mechanism
    • HSV produces
      • α protein → stimulates early genesβ protein
        • helps in DNA replication
      • late genesγ proteins
        • helps in viral structural proteins and Virion assembly

Clinical ulcers

  • Painful ulcers
    • HSV 2
    • Haemophilus ducreyi
  • Painless ulcers
    • Syphilis
    • LGV
    • Klebsiella granulomatis (Donovanosis)
      • notion image
  • HSV-1 and HSV-2
  • Tendency to get latent
    • Latent in dorsal root ganglion
  • Types of Infection:
    • Primary Infection:
      • First time virus infects;
      • usually more severe
    • Latent Infection:
      • Patient has no symptoms but can transmit
    • Recurrent Infection:
      • Virus reactivates
      • less severe
HSV-1 (typically above waist)
HSV-2 (typically below waist)
Primary Transmission
Mucosal or abraded skin contact
Sexual contact
Vertical
Site of Latency
Trigeminal ganglia
Sacral ganglia
M/c Age of Primary Infection
Childhood
Sexually active adults
Classic Clinical Presentations
Orofacial herpes (cold sores)
Herpetic gingivostomatitis
Herpes labialis
• Skin lesions above waist
(herpes gladiatorum, eczema herpeticum)
Herpes encephalitis
Genital herpes
• Skin lesions below waist
Neonatal herpes
Aseptic meningitis (Mollaret’s)
Most Common Site
Buccal Mucosa
Most Common 1° Lesion
Gingivostomatitis
Most Common Recurrent Lesion
Herpes Labialis

CNS Infections

  • HSV1 >> HSV2
    • HSV1 → M/c/c of encephalitis (temporal lobe)
    • HSV2 → M/c/c of meningitis
      • Mollaret's meningitis
      • Recurrent lymphocytic meningitis

Different Infections Caused by HSV:

Herpetic Gingivostomatitis:

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  • Most common cause of gingivostomatitis in children
  • Primary infection, very severe
  • Presentation: Multiple painful erosions in oral mucosa
  • Difficulty in eating, swallowing
  • Fever, lymphadenopathy may be present
  • Erosions coalesce together

Herpes Labialis:

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  • Recurrent infection (not primary)
  • Virus settles in trigeminal ganglion
  • Develops during: fever, stress, menstrual cycle
  • Small vesicles, coalescing together
  • Not very painful, discomfort
  • Also called cold sore
  • Usually on vermilion border of the lips
  • Very recurrent; milder
  • Just use topicals

Herpetic Whitlow:

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  • Healthcare worker handling forensic/dead samples
  • Virus inoculated on fingertip
    • Shows coalescing erosions
  • Mnemonic: Herpetic whitlow → herpes in white coat (Whitlow) → healthworkers

Other conditions

  • Herpes gladiatorum (wrestlers)
  • Erythema multiforme
  • Herpetic whitlow (healthcare workers)

Herpes Genitalis

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  • Ulcer Characteristics:
    • Multiple, painful.
    • Vesicles and coalescing erosions (ulcers not typical).
  • Incubation: Short (2-7 days)
  • Episodes:
    • Primary: More painful, severe.
    • Recurrent: Less painful, severe, intense.
  • Latent in dorsal root ganglion
  • Lymphadenopathy: Bilateral painful.

Herpetic Keratitis

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  • Treatment:
    • 3% Acyclovir eye ointment (not drops)
    • Steroids are contraindicated.
    • Eye drops 1st → Ointment 15 mins later.
      • If ointment is applied first:
        • It creates a barrier.
        • Prevents absorption of the eye drop.

NOTE
Similar terms
Seen in
Dendritic ulcer
HSV 1 Corneal ulcer
Pseudodendrites
Acanthameba
Pseudodendritic ulcer
Varicella Zoster

Diagnosis of Herpetic Infections:

EEG

  • Periodic lateralized epileptiform discharge (PLED)
    • Seen in HSV encephalitis
      • Mnemonic: His wife → Period late → she seizures
        • HSV Encephalitis → Affects temporal lobes
DOC is Acyclovir.
Mnemonic: HSV → His Wife → Like temples (temporal lobe)
          HSV Encephalitis → Affects temporal lobes
          DOC is Acyclovir.
          Mnemonic: HSV → His Wife → Like temples (temporal lobe)

Lab Diagnosis

  • Tzanck smear → Lipschultz bodies
  • Skin scrapings can be used
  • Geimsa staining
    • Cytopathic effect = 3M
      • Multinucleated
      • Molding
      • Margination
  • Mc coy culture
HSV Inclusion bodies
HSV Inclusion bodies

Tzanck Smear:

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  • Mnemonic: HSV → His Wife → Has Giant boobs (Multinucleated giant cell) and good lips (Lipschultz) → She wears tank top (Tzank) → She goes to Gym too (Giemsa stain). She becomes a target for others (Target lesions → erythema multiforme)
  • For cytology
  • Unroof vesicle/bulla or scrape erosion base
  • Stain with Giemsa stain
  • See: Large multinucleated giant cell (feature of HSV infection)
  • Also some acantholytic cells
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Gold Standard:

  • PCR (differentiates HSV 1 & 2).

Treatment of HSV Infection:

  • Treatment available: 
    • Acyclovir
    • Valacyclovir
    • Famciclovir
  • Primary infection:
    • Antiviral
      Dosage
      Duration
      Total/day
      Acyclovir
      200 mg x five times a day
      OR
      400 mg 3 times/day.
      7 to 10 days
      1g
      Valacyclovir
      1 g x twice times a day
      7 to 10 days
      2g
  • Recurrent infection:
    • Antiviral
      Dosage
      Duration
      Total/day
      Acyclovir
      400 mg x three times a day
      5 days
      1.2 g
      Valacyclovir
      1 g x twice times a day
      5 days
      3 g
  • If > 6 recurrences/year: 
    • suppressive treatment (daily)
  • If Acyclovir resistant:
    • Use Foscarnet and Cidofovir
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Hutchinson's

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  • HHerpes Zoster Ophthalmicus
  • UsubUngual Melanoma (superficial spreading melanoma)
    • Hutchinson sign
      • notion image
  • TTriad congenital syphillis
    • Peg shaped teeth
    • Interstitial Keratitis (IK + SNHL)
    • SNHL
  • CH Chauffeur's Fracture/Backfire Fracture
    • Intra articular #
  • Son looking olderHutchison Gilford
    • LMN A gene defect (laminopathy).
    • Progeria (onset: Child)
  • PUPIL Hutchinson Pupil
    • Herniation of uncus (medial temporal lobe) → compresses ipsilateral CN III → same side pupillary dilatation.
    • Kernohan’s notch phenomenon:
      • False localizing sign
        • Ipsilateral pupil dilatation
        • Ipsilateral UMN palsy

Complications of HSV Infection:

Erythema Multiforme (EM):

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  • HSV resolves, then target lesions develop on body
    • "Multiforme" due to multiple forms in same lesion
  • Causes
    • Most common infectious cause is HSV
      • Infection is the most common cause
    • Also Drugs
  • Target lesions: Three zones
    • Central zone of necrosis
    • Surrounded by oedema
    • Further surrounded by erythema
  • Usually preceded
    • HSV infection in >90% cases
    • drugs (10%)

Eczema Herpeticum / Kaposi's Varicelliform Eruption:

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  • Pre-existing dermatosis (Atopic Dermatitis, Darier's disease, Pemphigus)
  • Patient develops numerous vesicular lesions over these
  • Can be painful, associated with fever, crusting
  • Important point: 
    • Treat with Acyclovir
    • Do not treat with oral steroids (not exacerbation of Atopic dermatitis)
  • Pointers:
    • Dermatosis then numerous vesicular lesions on top

Mollaret's meningitis

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  • CSF: Monocytes, clefted nuclei (Mollaret cells).
  • Variant of aseptic meningitis.
  • Virus: HSV-2.
    • Causes recurrent aseptic meningitis.

Leading viral encephalitis

  • India: Japanese B.
  • worldwide: Herpes simplex.

Herpesviridae & Other Viruses

Varicella / Chickenpox:

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Smallpox Rash
Chickenpox Rash
Deep seated
Superficial
No area of inflammation around the rash
Area of inflammation around rash
Centrifugal
Centripetal
Palms & Soles not spared
Palms & Soles Spared
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Feature
Chicken Pox (HSV 3)
Measles
Etiology
Varicella zoster virus
SSRNA virus
(Paramyxoviridae family)
Age of Incidence
1-10 years (Peak age)
6 months - 3 years (Peak age)
Incubation period
14-16 days
10-14 days
Mode of Transmission
Airborne, droplet
Period of Communicability
2-3 days before → 4-5 days after
4-5 days before → 4-5 days after
Isolation period
Till all scabs or crusts are formed (6-7 days)
7 days from onset of c/f.
Secondary attack rate
85-90%
Case fatality rate
<1%
Clinical features
- Fever 
- Vesicular
("dew drop on a rose petal")

Lesions usually painless, but itching
- Fever 
-
Maculopapular rash:
starts behind the ear. 
- Koplik spots
(
Pathognomonic lower 2nd molar)
- Conjunctivitis (m/c) 
- Diarrhea
Rash progression
Centripetal
(starts on trunk, then face & limbs)

then
centrifugal to flexor surfaces

Rapid,
crops appear in batches
Fever with each new crop

All stages seen simultaneously:
macule → papule → vesicle → crust

Rash is
pleomorphic, morbilliform (red coloured)

Rash mostly on flexor surface
4th day of fever
Starts behind ears → face → trunk → limbs (cephalocaudal, centrifugal)

rash fades in 7 days in same progression leaving behind a brownish discolouration.
Complications
M/c
Secondary bacterial skin infection


Neonates/Immunocompromised
:
1.
Varicella pneumoniamost serious (esp. in pregnancy)
2.
CNS involvement
(benign cerebellar ataxia)


Congenital varicella syndrome:
• Infected during
early pregnancy 
Microcephaly 
Micro ophthalmia 
Low birth weight 
Atrophy of limbs 
Deafness
- Otitis media (m/c in children) 
- Diarrhea (m/c overall)
-
Pneumonia (m/c causing death) 
-
Sub acute sclerosing panencephalitis (SSPE): Long term Rare.
Associations
-
- Malnutrition 
-
Vitamin A deficiency

Herpes Zoster: Shingles

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  • In adults
  • Caused by reactivation of the virus
    • VZV settles in dorsal root ganglia after chickenpox
    • Reactivates due to Elderly, immunodeficiency, chemotherapy, etc.
  • Manifests along a particular dermatome
    • Unilateral, segmental (dermatomal) with midline demarcation
    • Most common dermatomes:
      • thoracic
      • D3–L2
    • Very, very painful vesicles
  • Clinical features same as varicella (erythema, coalescing vesicles, crust)
    • but located along dermatome
  • Can spread through touch
  • Complications:
    • Post Herpetic Neuralgia (most common, localized pain)
    • Zoster Ophthalmicus

Herpes zoster oticus / Ramsay hunt syndrome

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Ramsay-Hunt Syndrome
Ramsay-Hunt Syndrome
  • Involves reactivation of herpes zoster virus.
  • Virus remains latent in
    • Geniculate ganglion, CN 7
  • Presents with
    • Vesicles in facial nerve distribution (EAM)
    • LMN type of facial palsy.
    • SNHL due to 8th nerve involvement.
    • Otalgia
    • Loss of taste in anterior 2/3 tongue

Treatment:

  • Antiviral therapy: Acyclovir, Valacyclovir.
  • Topical agents and lotions for vesicles.
  • Steroids (+/-).

Facial nerve palsy is seen in

  • Malignant otitis externa
  • Ramsay Hunt syndrome
  • Keratosis obturans
  • Bell’s Palsy
  • MRK facial N palsy

NOTE: Referred Otalgia

Lesion Site
Nerve involved in referred pain
Oral lesions /dental caries
5th nerve (V3)
Oropharyngeal lesions / Tonsil
9th nerve (Glossopharyngeal)
Hypopharyngeal & Laryngeal lesions
10th nerve (Vagus)

Bell’s palsy

Bells Palsy
Bells Palsy
  • Idiopathic facial nerve palsy.
  • Seen in pregnancy, diabetics.
  • Associated with EBV and HSV.
  • Clinical features:
    • Deviation of angle of mouth.
    • Loss of nasolabial fold.
    • Sagging of eyebrow.
    • Hyperacusis

Herpes Zoster Ophthalmicus:

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  • If in trigeminal root ganglion
  • Hutchinson's Sign
    • Vesicles along ala of nose
    • Means nasociliary nerve involved 
      • (branch of ophthalmic division of trigeminal nerve)
    • Patient will have ophthalmic manifestations
    • ophthalmology referral needed

Treatment of Herpes Zoster:

  • Most painful, so highest dose of antivirals
    • Antiviral
      Dosage
      Duration
      Total/day
      Acyclovir
      800 mg x five times a day
      7 to 10 days
      4g
      Valacyclovir
      1g x three times a day
      7 to 10 days
      3g
  • Need painkillers, B12, etc.

NOTE
Similar terms
Seen in
Dendritic ulcer
HSV 1 Corneal ulcer
Pseudodendrites
Acanthameba
Pseudodendritic ulcer
Varicella Zoster

Post-Herpetic Neuralgia (PHN):

  • If neural manifestations persist after Herpes Zoster
    • Skin subsides, but pain persists
  • Duration:
    • After one to three months (variable definitions)
  • Symptoms: 
    • Persistent pain, paraesthesias, tingling, heaviness
  • Treatment: 
    • Tricylic Antedepressants >>
    • Pregabalin or Gabapentin

Hutchinson's

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  • HHerpes Zoster Ophthalmicus
  • UsubUngual Melanoma (superficial spreading melanoma)
    • Hutchinson sign
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  • TTriad congenital syphillis
    • Peg shaped teeth
    • Interstitial Keratitis (IK + SNHL)
    • SNHL
  • CH Chauffeur's Fracture/Backfire Fracture
    • Intra articular #
  • Son looking olderHutchison Gilford
    • LMN A gene defect (laminopathy).
    • Progeria (onset: Child)
  • PUPIL Hutchinson Pupil
    • Herniation of uncus (medial temporal lobe) → compresses ipsilateral CN III → same side pupillary dilatation.
    • Kernohan’s notch phenomenon:
      • False localizing sign
        • Ipsilateral pupil dilatation
        • Ipsilateral UMN palsy

Epstein Barr Virus (HSV 4)


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  • Primary disease: Infectious Mononucleosis
    • Also called Glandular Fever or Kissing Disease
  • Ballerina () + Paul
    • Ballerina
    • Naughty → NAHT
      • says 21 (CD21) yr → actually 18 (8 T cell)
    • Kissed → EBV
    • Down there → Downey, Duncan
    • Hairy → Hairy cell leukemia
    • then abdomen (Gastric cancer > Nasopha)
    • then neck (Nasopha)

Pathogenesis

  • Polyclonal B cell activation
  • Entry: via CD21/Cr2 receptor
  • Molecules:
    • LMP 1
    • EBNA 2 (activates SRC proto-oncogenes)
    • vIL10 (anti-inflammatory)
    • notion image

Skin manifestation:

  • Patients present with fever, lymphadenopathy, sore throat
    • misdiagnosed as bacterial
    • Given antibiotics (usually Amoxicillin or Ampicillin)
  • Develop an exanthem on body called Ampicillin rash
  • Mnemonic: Kiss cheythapo hairl ayipoi

Malignancies

  • Carcinomas:
    • M/c: Gastric carcinoma
    • Nasopharyngeal carcinoma
  • Lymphomas:
    • Hodgkin’s (mixed cellularity)
    • Non-Hodgkin: Burkitt’s, DLBCL, Post-transplant lymphoma
  • Sarcomas: Leiomyosarcoma

Other conditions

  • Duncan Syndrome (lymphoproliferative syndrome)
  • Hairy cell / Oral leukoplakia

Lab Diagnosis

  • Microscopy:
    • Atypical lymphocytes (Downey cells)
      • = CD8 T lymphocytes (Cytotoxic T cells)
    • "Ballerina skirt appearance"
      • notion image
  • Heterophile antibody detection:
    • Paul Bunnell Test (older)
    • Monospot Test (newer)
    • notion image
  • Specific Antibody Tests:
    • Viral capsid antigen
    • Early antigen
    • EBNA
  • Most sensitive & specific:
    • Nucleic Acid Hybridisation Test

Treatment

  • Acyclovir
  • Rituximab

Oral Hairy Leukoplakia

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  • Seen in HIV-positive patients
  • On lateral borders of the tongue
  • Hairy because of hair-like projections (white)
  • EBV
  • Acyclovir → for oral hairy leukoplakia

Cytomegalovirus (HHV 5)

Virus
Receptors
CMV
Integrins
(heparan sulfate)
Integrate with CM
Parvovirus B19
P antigen on RBCs
Rabies
Nicotinic AChR
Rhinovirus &
Falciform Malaria
ICAM-1
I went with a Camera (ICAM) and shoot False (Falciform M) Rhino () (Human in Rhino attire)
SARS-CoV-2
ACE2
Measles
CD150 and PVRL4.
PVR() il 150() rs nu CD() itt kanum
EBV/ HHV 4
CD21
HHV 6
CD46 on T cells
  • Largest of Herpesviridae
  • SRK (salivary, resp, kidney) → Largest → lives in mannat (Monocytes) → big muscle fibre (human fibroblast culture)
  • Reservoir: Humans only
  • Transmission:
    • Common: oral, respiratory, body secretions
    • Less common: transplacental, sexual
  • Multiplication sites (mnemonic SRK in Mannat):
    • Salivary gland
    • Respiratory tract
    • Kidney
  • Latent in: Monocytes
  • M/c infection during 1st 4 months of organ transplant

Infections

Infections
Features
Congenital
M/c intrauterine infection
Defects:
mental retardation
microcephaly
periventricular calcification
chorioretinitis
Perinatal
usually asymptomatic
Immunocompromised
CMV chorioretinitis
Immunocompetent
IMN-like syndrome
Features: fever, sore throat
No lymphadenopathy, splenomegaly, or specific antibodies

Features`

  • 1st CMV infection30%.
  • 2nd CMV infection1-2% (Developing countries like India).
  • Congenital CMV
    • 90% ofasymptomatic
      • No use of routine screening.
    • Most important long-term sequelae in SYMPTOMATIC CMV
      • Sensorineural hearing loss.
      • Most common non syndromic causes of hearing loss.

Clinical features in Congenital CMV

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Urine PCR > Saliva
Urine PCR > Saliva
  • Microcephaly
    • < 3 SD of HC
  • Chorioretinitis.
  • Hepatosplenomegaly.
  • Jaundice.
  • Petechiae.
  • Periventricular calcifications.

CMV Ocular

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  • Most common cause of vision loss in ocular HIV.
  • Mnemonic:
    • CMV → Come we have Pizza, scrambled egg and ketch up,
    • So brush and come

Features:

  • "Pizza pie" appearance.
  • "Scrambled egg and ketchup" appearance.
    • notion image
  • "Brushfire extension" pattern.
    • notion image
  • Causes focal chorioretinitis.
PCR of both aqueous and vitreous humor
PCR of both aqueous and vitreous humor

Diagnosis

  • Congenital CMV
    • Demonstrate replicating virus within the first 3 weeks.
      • PCR/Viral culture:
        • Best sample - urine sample.
        • It can be done using saliva or blood sample.
    • CMV IgM:
      • ELISA
      • Cannot demonstrate replicating virus
  • Owl eye inclusion bodies (intra-cytoplasmic + intra-nuclear)
    • notion image
  • Virus isolation:
    • human fibroblast cell lines (secondary)
    • specimen = urine washing
  • Detection: PP65 antigen
  • PCR

NCCT

  • Periventricular Calcification.
    • notion image
  • Note:
    • ZikaWhite and grey matter calcification
    • ToxoplasmaCerebral calcification

Treatment for symptomatic patients

  • DOC: Ganciclovir
    • Resistance d/t U97 phosphotransferase gene
  • Resistance: Foscarnet
  • Note:
    • UL 57 (DNA Polymerase) causes resistance to Ganciclovir, Foscarnet and cidofovir

HHV-6/HHV-7 (Roseola infantum)

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  • Receptor: CD46 on T cells
  • Variants: 6A, 6B
  • Transmission: Oral secretions (“SIXcretions”)
  • 6 Nagas → 46 → SIXcretions → 6A 6B → Sixth disease

Children:

  • Sixth disease / Roseola infantum / Exanthem Subitum
    • "Roseola" ⇒ rose-coloured/red rash
    • "Infantum" ⇒ infants ⇒ < 2 years
    • "Exanthem" ⇒ rash
    • "Subitum" ⇒ sudden
      • Sudden eruption of fever
      • Fever subsidessudden appearance of rash
  • Features:
    • fever
    • Nagayama spots (soft palate + uvula),
      • notion image
    • rose-pink non-pruritic rash (appears after fever subsides)

Adults:

  • Mononucleosis-like syndrome

HHV-6/HHV-7 (Pityriasis Rosea):

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  • "Pityriasis" ⇒ scaly
  • "Rosea" ⇒ red
  • History of URTI or GI tract infection 
    • two weeks prior
    • F/b a single patch on the trunk 
      • called Herald Patch or Mother Patch
      • Erythematous plaque with a collar of scales (collarette of scales)
  • After Herald Patch, two weeks later
    • numerous small erythematous plaques all over the trunk
    • Typically along the lines of cleavage
    • "Christmas Tree" or "Fir Tree pattern"
  • Self-resolving condition,
    • Resolves in four to six weeks
  • Important:
    • Herald patch, collarette of scale, Christmas/Fir tree pattern, caused by HHV-6/HHV-7
  • girlfriend : its pity () that u suddenly (sudden → roseaseola infantum) brought 6-7 rose in Christmas day
  • boyfriend : dont worry dear, 6-7 christmas tree () is coming
  • (herald patch appears early then comes fir tree pattern - affects young adults (gf bf))

Human Herpesvirus 8

Associated disease:

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  1. Kaposi Sarcoma (vascular tumor)

      • Association: Seen in HIV-positive individuals
      • Gamma virus
      • Most Common Sites:
        • First: 
          • Seen on legs
          • Presents with deep red to bluish papules and nodules
        • Second: Lymph node.
          • notion image
      • M/c lid malignancy in HIV
      • Microscopy:
        • Shows spindle cells.
      • IHC (Immunohistochemistry): 
        • LANA (latency associated nucleic acid) positive.
      • Kakkusil pokumbo sing LALA (LANA) and SPIN (Spindle)

  1. Primary Effusion Lymphoma
      • Effusions (pleural, pericardial)
      • CD30 & CD38 +ve
        • notion image
  1. CASTLEMAN Disease
      • Site: lymph nodes
      • Symptoms: B cell symptoms (fever, night sweats, weight loss)
      • Histology:
        • "Onion skinning of lymphocytes"
        • "Lollipop follicles"
          • notion image
A patient presents with abdominal distention and intermittent fever. Peripheral smear findings are normal. A tumor is resected and the histopathology image of the resected lymph node is shown below. What is the most probable diagnosis ?
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A. Angiolymphoma
B. Hodgkin’s lymphoma
C. IgG-4 related disease
D. Castleman disease
ANS
Castleman disease
 

Kaposi Sarcoma

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  • Cause: Human Herpes Virus 8 (HHV-8).

Parvoviridae

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  • Smallest virus (20 nm)
  • Only single-stranded DNA virus
  • Structure: icosahedral symmetry
  • Transmission: respiratory, blood transfusion, transplacental
  • Target: P antigen of RBC precursors (mnemonic: PAR)

Parvovirus B19

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Erythema Infectiosum (5th disease):

• Parvovirus attach to P Ag of RBC Precursors
• Leads to Pure red cell Aplasia (PRCA)
Parvovirus attach to P Ag of RBC Precursors
Leads to Pure red cell Aplasia (PRCA)
  • Pavam → Small size → husband died and single (ssDNA) → got slapped () with 5 (5th disease) fingers, have a dog
  • "Slapped Cheek Appearance"
    • Macular rash on cheeks
  • Lacy rash on rest of body
  • Well child, no fever + sore throat
  • Self-limiting
  • Microscopy
    • Dog ear projections
    • Shape
      Alias
      Seen In
      Acanthocytes
      Spur cells
      Abetalipoproteinemia 
      (A for A)
      Echinocytes
      Burr cells
      Burns,
      Renal failure,
      Pyruvate kinase deficiency
      EDTA changes (BUE)
      BURP
      Burr → Burn → Pyro → PK def
      Dacrocytes
      Teardrop RBCs
      Myelophthis
      Myelofibrosis
      Schizocytes
      Helmet cells
      MAHA
      Micro: HUS/TTP/DIC/HELLP
      Macro: Prosthetic valves
      Dog ear projections
      Parvovirus B19
      Leads to PRCA
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Can also cause:

  • Arthropathy
  • Transient aplastic crisis → in hemolytic anemia
  • Persistent kind of anaemia
  • Pure red cell aplasia → associated with thymoma
  • M/c/c of infectious Non immune Hydrops fetalis with congenital anaemia
  • Papulo Pruritic Gloves & socks syndrome (PPGS)
  • Mnemonic: Parvo → Paanch → anju viral vach mugathadich

Hand, Foot and Mouth Disease (HFMD)

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  • Enteroviral disease
  • Picorna virus
    • family of RNA viruses
    • Caused by Coxsackie A16 and Enterovirus 71
Condition
Coxsackie
Enterovirus
HFMD
A16
71
Acute hemorrhagic Conjunctivitis
A24
70
  • Affects hand, foot, and mouth
  • Manifests with vesicles with an erythematous border on these areas
  • May have fever and constitutional symptoms
  • Mnemonic: Ente (Enterovirus) cock (coxackie) → in your handum mouthum (HFMD)

HFMD Other causes

  • CaRS
    • Coxackie A16
    • RMSF
    • Secondary syphilis

Herpangina

  • Causative agent: Enterovirus 71
  • Vesicles are present on the oral mucosa of the palate
  • Mnemonic: Her pan angina → mouthilu pain → Ente cock
    • notion image

Note: Causes of AFP

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  • Poliomyelitis
  • Guillain-Barré syndrome
  • Traumatic neuritis
  • Traumatic myelitis
  • Enterovirus A71

Papovaviridae

  • Includes: Papilloma Virus (HPV), Polyomavirus

Polyomaviruses

Virus
Notes
Merkel Cell Virus
Merkel Cell Carcinoma (neuroendocrine skin tumor)
SV40
Mesothelioma
Save size 40 Meesa
JC Virus
Progressive Multifocal Leukoencephalopathy
Junkie Cerebrum (HIV AIDS)
BK Virus
Post kidney transplant
Bad Kidney
Urine microscopy:
large nuclei cells mimicking cancer = Decoy cells
  • JC () saved 40 () people from Bad Kidney Virus () → Marakkallee (Merkel cell virus)
    • Decoy cells
      Decoy cells

HPV

  • Type: Epitheliotrophic.
  • Causes warts or verruca
  • HPV has 200 subtypes

Histology: 

  • Koilocytosis with biopsy indicates CIN 1.
  • (Koilocyte is pathognomic for SCC insitu)

Cutaneous involvement:

  • HPV 1, 2, 3 → low-risk skin warts
    • D: Deep Plantar (HPV 1)
    • S: Superficial Plantar (HPV 2)
    • P: Plain Warts (HPV 3, 10)
  • HPV 5, 8 → high-risk skin warts
    • Epidermodysplasia Verruciformis / Tree man syndrome
      • chr. 17 defect
      • 58 year old tree man with 17 year old girl
      • notion image
  • Buschke's Warts

Mucosal involvement:

  • HPV 6, 11 low-riskmucosal & genital warts (Condyloma Acuminatum)
    • Leads to:
      • Laryngeal papillomas.
      • Genital warts
        • Pregnancy → DOC → Trichloracetic Acid
      • Mnemonic:
        • Pregnant avumbo war (wart) vanna → Ace the war (Trichloroacetic acid)
        • 6 ⇔ G (genital warts) ;
        • 11 (LL ⇔ Laryngeal papiLLomas)
  • HPV 16, 18, 31, 33, 45, 52, 58high-risk
    • 1618.3133.4552.58
    • Cancers caused by HPV:
      • Male - penile, oral, anal
      • Female - cervix, vagina, vulva
    • Cervical cancer
      • Most common serotype - HPV 16
      • Most malignant serotype - HPV 18
      • Most specific serotype - HPV 18
      • Most common serotype associated with
        • Cervical Squamous cell carcinoma - HPV 16
        • Cervical Adenocarcinoma - HPV 18
    • Anal cancer
      • HPV16
    • Oropharyngeal cancer
      • HPV16
    • Genital cancers / Penile, vulvar, vaginal cancers
      • HPV16
Wart Type
Characteristics
HPV Types
Plantar Warts
• On feet;
• may be
painful
Superficial/mosaic pattern (HPV 2)
Deep: 1;
Superficial
: 2
Plain Warts /
Verruca Plana
flat-top, hyperpigmented papules on face;
(not hyperkeratotic)
• Common in
immunocompromised or HIV state
3
Common Warts /
Verruca Vulgaris
• Generally painless;
verrucous or hyperkeratotic papules;
asymptomatic;
anywhere on body
Pseudokoebner's phenomenon is positive
4, 2, 27
Epidermodysplasia Verruciformis (EDV)
Genetic tendency to widespread HPV;
autosomal recessive
Increased SCC risk;
Pityriasis versicolor-like,
Plain warts,
• Reddish plaques
5, 8
Anogenital Warts /
Genital Warts /
Condyloma Acuminata
Flat base, pointed;
STI
Giant Condyloma Acuminata
Buschke-Löwenstein Tumour
Bushinte lowerside ilu accumulated
6, 11;

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HPV
HPV

Structure & Function:


Protein
Notes
L1 capsid protein
Vaccine development
L → Live vaccine
E1 & E2
Proteins needed for viral replication
2 → To Control
E2
Controller
E4, E5
Cell changes → koilocytes
(raisin nucleus + perinuclear halo)
4, 5 Condoms
E6, E7
Carcinogenesis
↳ E6
inactivates p53 (policeman)
6 → 5 → 3;
P ⇔ 6
↳ E7
inactivates RB (governor gene)
Seven → S → SRB → RB

HPV Vaccines

  1. Nonavalent (Gardasil 9, in USA):
      • Active against HPV types 6, 11, 16, 18, 31, 33, 45, 52, 58.
      • Protects against Genital Warts and all Cervical/Anal/Vulvar/Vaginal Cancer (HPV).
  1. Quadrivalent (Gardasil/Cervavac):
      • Active against HPV types 6, 11, 16, 18.
      • Protects against Genital Warts and Cervical Cancer.
      • Mnemonic: 4 vaakku parayamo
        • Cervavac

        • India's first vaccine against cervical cancer.
        • Developed by Serum Institute of India, Pune.
  1. Bivalent (Cervarix):
      • Active against HPV types 16, 18.
      • Protects against Cervical Cancer.
      • Mnemonic: 2 vari padamo
      notion image
       

Recent update

  • Prevent head & neck & Oropharyngeal cancer by HPV

PYQS for HPV Vaccine

  • Ideal Age: 11-12 years.
  • Age Group (Good): 9-26 years.
    • Cervavac can be given only till 26 yrs due to lack of testing
  • High Risk Age: 27-45 years.
  • C/I: Pregnancy.
  • WHO SAGE Recommendation:
    • 9 to 20 years old: 1 or 2 doses.
    • Over 21 years old: 2 doses.
    • HIV positive: 3 doses.
  • Common Side Effect: Syncope.
  • Vaccines made from: L1 capsid proteins.

HPV Vaccine can be given to:

  • HIV Positive Females.
  • HIV Positive Males.
  • Sexually active females.
  • Boys.
  • HPV testing before vaccine: Not recommended.
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Different Kinds of Warts:

Common warts/Verucca vulgaris
Common warts/Verucca vulgaris
Plantar Warts
Plantar Warts
Anogenital Warts → acuminata
Anogenital Warts → acuminata
 
 Verruca plana
Verruca plana
Epidermodysplasia Verruciformis (EDV)
Epidermodysplasia Verruciformis (EDV)
Condyloma Acuminata
Condyloma Acuminata

Histopathology of Warts:

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Koilocytes

  • Modified keratinocytes
  • Have a pyknotic nucleus
  • Around nucleus, a clear space (perinuclear halo)
  • Features of HPV or Verruca
  • Kozhitharam (koilocytes) arnn → HPV vannu → Now no one around him (peri nuclear halo)
  • Ellarum veruthu (verucc) →
  • Both →
    • Plane face (verucca plana → on face) → Black colored (Hyperpigmeted)
    • Vulgar body (verucca vulgaris → anywhere in body) → ↑↑↑ skin thickness in body

Treatment of Warts:

  • No oral medicine which can kill HPV
    • Immunomodulators 
      • Cidofovir, Oral Retinoids, Zinc
      • used in HIV-positive patients or severe warts
  • physical and chemical methods
    • Common therapies: (Also Preferred in pregnancy)
      • Cryotherapy
      • Lasers
      • Electrocautery
      • TCA (Trichloroacetic Acid)
    • Podophyllin: Generally for genital warts
    • Imiquimod
    • Topical 5-Fluorouracil
    • Salicylic acid: Used for plantar warts

Inverted Papilloma

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  • Benign, pre-malignant condition.
  • M/c site Middle Meatus
  • Arise from pseudostratified columnar epithelium (Schneiderian membrane)
  • A/w Human Papilloma virus (HPV).
  • Also called:
    • Transitional cell papilloma.
    • Ringertz tumor.
    • Schneiderian papilloma.
  • Locally invasive.
  • Premalignant
    • Associated with malignancy in 5 - 10%.
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Clinical features:

  • Blood stains in nasal discharge.
  • Nasal obstruction.
  • Projections from lateral wall of nose.

Histopathology:

  • Finger-like projections grow towards stroma.
    • notion image
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Treatment:

  • Medial Maxillectomy
    • via lateral rhinotomy / midfacial degloving approach
    • Endoscopic > External approach
    • Remove:
      • Lateral wall of nose
      • Medial wall of maxilla
  • Recurrent:
    • Cidofovir
  • Avoid radiotherapy ⇒ turns malignant

CT Scan

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Adenovirus

  • Morphology:
    • Space vehicle-shaped
    • non-enveloped
Infections
Serotypes
Hemorrhagic Cystitis
serotype 11, 21
Hemorrhagic: 11 alphabets → 11, 21
Infant diarrhea
serotype 40, 41
Potty 40
Eye infections
Epidemic keratoconjunctivitis (EKC) /
Shipyard eye:
↳ serotype 8, 19, 37

Pharyngoconjunctival fever (PCF) /
Swimming pool conjunctivitis:
↳ serotype 3, 7, 14
Shipyard eye

3rd day → floating
7th day → basic
14th day → advanced
Respiratory
• URTI: 1, 2, 3, 5
• Pneumonia:
3, 7, 21
• Transplant infections:
34, 35
Upper → 123
Lower → 3, 7, 21
Transplant at 30
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Viral Conjunctivitis:
Adenoviral
Epidemic keratoconjunctivitis (EKC)
↳ serotype 8, 19, 37
Pharyngoconjunctival fever (PCF) /
Swimming pool conjunctivitis:
↳ serotype 3, 7, 14

3rd day → floating
7th day → basic
14th day → advanced
Acute hemorrhagic/
Apollo conjunctivitis
PACE Mnemonic
Picornavirus
Adenovirus
Coxsackie A24
Enterovirus type 70
Others
Angular conjunctivitis: Moraxella
HSV conjunctivitis.
Molluscum contagiosum conjunctivitis.
Condition
Coxsackie
Enterovirus
HFMD
A16
71
Acute hemorrhagic Conjunctivitis
A24
70
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Hepatitis Viruses

  • partial dsDNA
  • Portal tract expansion
  • ALT > AST

Classification

  • Incubation period
    • A & E → 15 - 50 days
      • Both non enveloped
    • B & D → 50 - 150 days
    • C → 15 - 150
  • Only cultivable
    • Hep A
  • No vaccine
    • C (quasispecies) and E
  • All RNA
    • except Hep B partial dsDNA
(Mnemonic: Private Hospitals Favour Rich Clients)
Virus
Family
Transmission
Envelope
Vaccine
HAV
Picornaviridae (Enterovirus)
Feco-oral
Non-enveloped
HBV
Hepadnaviridae
Parenteral,
sexual,
MTC
Enveloped
HCV
Flaviviridae
Parenteral
Enveloped

(
quasispecies)
HDV
With HBV assist
Parenteral
Enveloped

(via HBV vaccine)
HEV
Hepeviridae (Calicivirus)
Feco-oral
Non-enveloped
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  • Precore mutantcannot produce HBeAg
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Important facts

Hep Virus
Notes
Extrahepatic Manifestations
HEV
MC cause sporadic acute hepatitis in India
25 % fulminant hepatitis in pregnancy
• [(1-2%) otherwise]
HDV
MC cause fulminant viral hepatitis
• (5-20%)
Co-infection:
↳ HBV + HDV simultaneously
Superinfection:
↳ HDV in pre-existing HBV patient
HBV
MC cause
transfusion hepatitis
chronic hepatitis, carrier state
hepatitis-causing cancer
Polyarteritis Nodosa (30%),
Membranous GN
HCV
Maximum chronicity risk
Strongest cancer association
Membranoproliferative GN,
Mixed cryoglobulinemia,
Lichen planus (colloid / civatte bodies)
Hepatitis G
No known human infection
• infects
mononuclear cells
• Transmitted via transfusion
protects against HIV

Hepatitis B:

  • Dane Particle (Hepadna virus)
  • DNA virus, partially double-stranded
  • Susceptible to
    • Hypochlorite
    • Heat labile
  • Reservoirs: Human.
  • Mode of transmission:
    • Parenteral: IV drug use.
    • Vertical: Mother to child.
  • Incubation period: 30-180 days.
  • Period of communicability: 
    • Till HBSAg +ve in blood.
  • Clinical features:
    • Low grade fever.
    • Icterus.
    • Malaise.
    • Clay stools.
Genome
P
DNA Polymerase
Reverse transcriptase + RNAase
C
HBcAg (core)
HBeAg (pre-core)
S
HBsAg
Australia Antigen, different sizes
Orcein Shikata Stain (eosinophilic appearance)
X
HBX
Carcinogenesis in liver
  • Pathogenesis
    • Ground glass hepatocytes (hazy cytoplasm)
    • Surface antigen
    • Orcein shikata
      • notion image

Prevention

HBV vaccine:

Feature
Description
Content
HBSAg 
Aluminium Hydroxide (Adjuvant)
Cold chain
2°C to 8°C (Freeze sensitive)
Dose
• Adult: 1 mL (10-20 mcg) 
• Birth:
0.5 mL
Duration of protection
Lifelong (After 3 doses)
Schedule
0, 1, 6 months (3 doses) 
• If
interrupted: Resume schedule
C/I
Anaphylaxis

Accidental Needle Prick

  • Timing: <2 h (up to 48h).
  • Dose: 0.05 - 0.07 mL/Kg in 2-3 doses.
  • Check HBSAg in the victim:
    • + ve: Don't give vaccine.
    • - ve:
      • HB Vaccine (Recombinant) + HbIg → both can be given
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WHO 5C's concept for prevention of Hepatitis B:

  • Consent.
  • Counselling.
  • Confidentiality.
  • Connection (For prevention, treatment and care services).
  • Correct test results.

Note

  • For Hep B
    • Orcein shikata stain
  • For Ceruloplasmin:
    • Orcein stain
  • Markers
    • Anti-HBsepidemiological marker
    • IgM anti-HBcwindow period marker
    • Anti-HBedecreased infectivity
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Treatment

  • LETLamivudine, Emtricitabine, Tenofovir
  • Latest guidelines: TEA
    • Tenofovir
    • Entecavir
    • Pegylated interferon-alpha (PEG-IFN-α)

Lab Diagnosis of HAV

  • Shedding:
    • Stool → 2 weeks before to 2 weeks after symptom onset
  • Antibodies:
    • IgM → with jaundice onset
    • IgG → appears 2–4 weeks later

Hepatitis C:

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  • Liver biopsy:
    • Grading = Inflammation + Necrosis (GIN)
    • Staging = Fibrosis
  • Fatty liver change
    • Show macrovesicular steatosis
    • with lymphoid aggregates
  • Ballooning degeneration (Swollen hepatocytes).
  • Bile duct proliferation
  • Councilman bodies 
    • apoptotic bodies
    • An Eosinophilic apoptotic body (pinkish small body).
      • Apoptotic bodies in Hep C
        Apoptotic bodies in Hep C
  • Lymphoplasmocytic infiltrates.
  • No portal inflammation.
  • Spotty necrosis.