EMQs in Clinical Medicine.pdf - Peshawar Medical College

Poisoning and overdose – answers 233
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J
C
L
F
This is a herpes zoster infection (shingles). Oral aciclovir is the treatment
of choice.
A 41-year-old HIV-positive man presents with decreased visual acuity.
Fundoscopy shows a ‘mozarrella and tomato pizza’ appearance.
Cytomegalovirus (CMV) retinitis usually occurs only when the CD4 count
has dropped to below 100. The diagnosis is made clinically. Fundoscopy
reveals a characteristic ‘pizza’ appearance caused by the appearance of
haemorrhages and exudates that follow the retinal vessels.
CMV retinitis is a medical emergency as a result of the risk of blindness
and should be treated with intravenous ganciclovir. Foscarnet can also
be used to treat CMV retinitis.
An infant is suffering from severe respiratory syncytial virus (RSV)
bronchiolitis.
Inhaled ribavirin is indicated, although there is not yet clear evidence
that it provides significant clinical benefit. A monoclonal antibody is
now available that can be used to prevent RSV infection in infants at
high risk (palivizumab).
A 40-year-old man with chronic hepatitis C infection.
Interferon- is given by subcutaneous injection. Combination therapy
with ribavirin is more effective and should be continued for 6 months.
Highly active anti-retroviral therapy for a 28-year-old
HIV-positive man.
AZT, didanosine and indinavir provide a combination of two nucleoside
sanalogue reverse transcriptase inhibitors (AZT, didanosine) with one protease
inhibitor (indinavir), which is commonly referred to as highly active
anti-retroviral therapy (HAART). Non-nucleoside analogue reverse transcriptase
inhibitors, e.g. nevirapine, can also be used as part of HAART.
89 Poisoning and overdose
Answers: K I C D M
K
A 25 year old is rushed to A&E presenting with vomiting,
hyperventilation, tinnitus and sweating. Blood gases show a
respiratory alkalosis.
Patients initially present with a respiratory alkalosis caused by
hyperventilation (stimulation of the respiratory centre) but a metabolic
acidosis may develop later.
Multiple doses of oral activated charcoal reduces the absorption of
aspirin and is more effective the earlier it is given.
Management of overdose can be classified according to
mild/moderate/severe overdose.