The most common etiological agent for retinitis in HIV infected patients is cytomegalovirus (88.63% of retinitis in HIV/AIDS patients). Most patients have a CD4 lymphocyte count less than 50/μL, which can represent the susceptibility to this type of retinitis when lymphocyte count falls below this threshold. The treatment consists of systemic intravenous administration of Ganciclovir or Foscarnet at a first stage of induction, followed by the maintenance treatment with oral administration of Ganciclovir.

Unprotected anal or vaginal sexual intercourse with an infected individual is by far the most common (95%) route by which HIV is transmitted. Other options:- Blood transfusion is an extremely rare cause of HIV transmission in the UK. – While HIV can be transmitted from mother to baby either during birth or via breastfeeding, the transmission rate is only 5 – 20%.- Sharing contaminated needles does put individuals at risk of getting HIV, although public health measures are in place to reduce this risk. – Although HIV can be transmitted via this route, it is around ten times less likely to result in transmission than unprotected anal or vaginal intercourse with an infected individual.

To prevent mother to child transmission in the case of an HIV infected mother, guidelines have been put in place in the that guide practices. During pregnancy the risk of intrauterine transmission is quite low, as is the risk of transmission during vaginal delivery. As a result the number of women that choose to have caesarean sections have fallen, with vaginal births increasing by 40%. One factor that can however increase the risk of mother to child HIV transmission is concurrent Hepatitis C infection which double the risk of vertical transmission.

The antiretroviral agent for the side effects mentioned is most probably, efavirenz.Efavirenz is a non-nucleoside reverse transcriptase inhibitor and the most likely cause of new-onset psychiatric symptoms in someone taking HAART. In this scenario the patient had no pre-existing mental health problems, as other antiretrovirals can cause depression and suicidal ideation in those who have a past psychiatric history. Symptoms usually subside after a few weeks of treatment.Other options:- Emtricitabine is a nucleoside reverse transcriptase inhibitor and is also not known to cause psychiatric side effects. The most common side effects of Emtricitabine are rash and darkening of the palms or soles.- Lamivudine is a nucleoside reverse transcriptase inhibitor, which can cause insomnia, but does not commonly cause other psychiatric symptoms.- Rilpivirine is a non-nucleoside reverse transcriptase inhibitor, which can cause depression. However, this is more common in those with a history of mental health problems.- Tenofovir is a nucleotide reverse transcriptase inhibitor. The most common side effect of Tenofovir is gastrointestinal upset. It is not known to cause psychiatric side effects.

According to the Rumack-Matthew Normogram, accurate levels of paracetamol can be measured only between 4-15 hours. The levels measured before 4 hours post-ingestion would highly underestimate the level of paracetamol ingested.The patient in question presents 2 hours after ingestion. Hence the most appropriate time to measure the levels of acetaminophen would be a further 2 hours later. Other options:- Note that the treatment with NAC can be delayed until the 4-hour level is obtained and compared to the nomogram.- Furthermore, haemodialysis is only indicated if she develops hepato-renal syndrome that is likely to occur 72-96 hours post-ingestion.- Indications for acute liver transplantation include persistent acidosis, hepatorenal syndrome and worsening coagulopathy.

Congenital TB symptoms typically develop during the second or third week of life and include poor feeding, poor weight gain, cough, lethargy, and irritability. Other symptoms include fever, ear discharge, and skin lesions.Signs of congenital TB include failure to thrive, icterus, hepatosplenomegaly, tachypnoea, and lymphadenopathy.

Patients with HIV have a deficiency of CD4 lymphocytes which are also known as helper T cells (Th). They are involved with antigen-specific responses as well as delayed-type hypersensitivity. The risk of developing P. jiroveci pneumonia is greatest with a CD4 count of 200 x 109/l or below.

Infants exposed to maternal HIV and with positive results require immediate management with co-trimoxazole prophylaxis, regardless of their CD4 levels. Antiretroviral treatment is necessary as well but it could wait until further work-up is complete.

Based on the presentation, she probably was administered co-amoxiclav.The liver function tests are highly suggestive of cholestatic jaundice, which is a classic adverse dug reaction related to co-amoxiclav use.Other options:- Erythromycin is more commonly associated with gastrointestinal (GI) disturbance.- Gentamicin is more commonly associated with renal impairment.- Meropenem does not commonly cause cholestasis but is associated with transaminitis.- Vancomycin is associated with red man syndrome on fast administration.

Recommended regimens3 NRTI (e.g., zidovudine, lamivudine, abacavir) OR2 NRTI (e.g., lamivudine + abacavir) AND1 NNRTI (e.g., efavirenz) OR1 PI (e.g., lopinavir) OR1 INI (e.g., raltegravir)