Tropical ophthalmology Flashcards
Name examples of HIV associated ocular conditions
HIV microangiopathy
OIs (HSV, VZV, CMV, TB)
Malignancies
- OSSN
- kaposi’s
- lymphoma
IRIS
What is OSSN?
Ocular surface squamous neoplasia
What are the characteristics of HIV microangiopathy and the treatment?
Retinal haemorrhages
Cotton wool spots
Microaneurysms
Treatment: ARVs
Why are OIs common in HIV?
- Increased susceptibility
- Increased reactivation of latent organisms
- Increased pathogenicity of organisms
What ocular manifestations can HSV cause?
Keratitis
Uveitis
Retinitis
What ocular manifestations can VZV cause?
HZ ophthalmicus
Keratitis
Uveitis
Retinitis
What ocular manifestations can CMV cause?
Uveitis
Retinitis
What is the clinical characteristic of HSV keratitis?
Dendritic appearance in cornea
What is significant regarding HSV keratitis in the HIV population?
Increased incidence
Increased severity
Can be bilateral
What is herpes zoster ophthalmicus?
Reactivation in the ophthalmic division of trigeminal nerve
Name risk factors for herpes zoster ophthalmicus
Older age
HIV
What is the clinical presentation of herpes zoster ophthalmicus?
Papules, vesicles, pustules, crusting
Hutchinson sign
Postherpetic neuralgia
Skin severity does not correspond with ocular severity
What is the chance of eye involvement if Hutchinson sign is observed?
80%
What is the management of herpes zoster ophthalmicus?
Oral acyclovir within 72h of rash
Oral steroids
Ophthalmologist referral for complications
Name long term complications of herpes zoster ophthalmicus
Neurotrophic keratopathy
Lid changes
At what CD4 is CMV retinitis most common?
Low Cd4
What is the characteristic appearance of CMV retinitis?
Characteristic margherita pizza appearance (vasculotrophic virus)
Discuss the management of CMV retinitis
ARVs
Ganciclovir (intravitreal or oral)
What is the spectrum of OSSN?
Conjunctival intraepithelial neoplasia
CiS (carcinoma in situ)
SCC (squamous cell carcinoma)
Name risk factors for OSSN and which has the highest pathogenecity?
UVB
HIV
HPV (highest pathogenicity)
Discuss treatment of OSSN
Excision
Tropical chemotherapy
Which virus is Kaposi’s associated with?
HH8
What is the management of Kaposi’s sarcoma?
ARVs
Which virus is lymphoma associated with?
EBV
What is the management of lymphoma?
Excision
Radiotherapy
Which virus causes molluscum contagiosum?
Poxvirus
What can be the complication of molluscum contagiosum?
Follicular conjunctivitis
Discuss the management of molluscum contagiosum
Conservative
Excision if non-resolving or conjunctivitis
What is ophthalmia neonatorum?
Conjunctivitis within 1st month of life
Name causes of ophthalmia neonatorum
C. trachomatis
N. gonorrhoea
HSV
Discuss management of ophthalmia neonatorum
Topical chloramphenicol
Saline irrigation of conjunctiva
Systemic ABs
- n. gonorrhoea IV CTX
- c. trachomatis PO erythromycin
- HSV IV acyclovir
What is the leading cause of preventable blindness?
Trachoma
Which pathogen causes trachoma and how is trachoma transmitted?
C. trachomatis A, B, C transmitted by direct contact or flies
What is the WHO grading of trachoma?
FIST
Follicular
Inflammation
Scarring
Trichiasis
Corneal opacity
Discuss management of trachoma
WHO SAFE strategy
- surgery
- antibiotics
- face cleanliness
- environmental improvement
Which antibiotics should be used for trachoma?
1g azithromycin stat to patient AND family
Repeat annually if endemic
What is ophthalmomyasis?
Infestation with fly larva, mostly in summer months when female fly releases larvae into eye
Discuss management of ophthalmomyasis
Removal
Ivermectin
Name the causative organism of leprosy
M. leprae
M. lepromatosis
What are the systemic features of leprosy?
- Tuberculoid
- Borderline (most common)
- Lepromatous
Describe tuberculoid leprosy
Hypopigmented macules
Anaesthetic skin patches
Describe borderline leprosy
Similar to tuberculoid but more numerous and extensive
Describe lepromatous leprosy
Widespread cutaneous thickening
Leonine facies
Peripheral plaques and nodules
URTI
Loss of digits due to peripheral neuropathy
Discuss the ocular features of leprosy
Anterior uveitis
Iris pearls
Keratitis
Pannus
Which fly transmits onchocerciasis?
Simulium black fly
What is onchocerciasis also called?
River blindness
How is onchocerciasis caused?
Black fly bites human -> larvae in nodules migrate to eyes
What is the maculopapular rash in onchocerciasis also called?
Leopard skin rash
What are the ocular features of onchocerciasis
Microfilariae in cornea/anterior chamber
Anterior uveitis
Keratitis
Chorioretinitis
Optic neuritis
Discuss management of onchocerciasis
Ivermectin
What causes neurocysticercosis?
Taenia solium
What are the ocular features of neurocysticercosis?
Cysts in conjunctiva, anterior chamber and vitreous
Discuss management of neurocysticercosis
Cyst removal
Anti-helminths
Steroids
What causes hydatid cysts?
Echinococcus species
What is the management of hydatid cysts?
Excision
Praziquantel
What is the function of vitamin A?
Maintain epithelial surfaces
Immune function
Retinal function
What is xerophthalmia?
Spectrum of ocular disease due to vitamin A deficiency
Name causes of xerophthalmia
Malnutrition
Malabsorption
Alcoholism
Diarrhoea
Measles
How is xerophthalmia classified?
XN - night blindness
X1 - conjunctival xerosis with Bitot spots
X2 - corneal xerosis
X3 - corneal ulceration
Xs - corneal scar
XF - xerophthalmic fundus
What is a bitot spot?
Keratinised triangular lesion seen with xerophthalmia
Discuss management of xerophthalmia
Vitamin A supplementation
- 200 000IU oral
- diet
Ocular
- lubrication
- structural support in case of perforation
What is ocular perforation in xerophthalmia also called?
Corneal melt
