Cryptococcal Antigenemia in South African Children Living With HIV.

BACKGROUND

Cryptococcal meningitis (CM) is associated with high mortality and neurodevelopmental sequelae and predominantly affects people living with HIV. Screening and pre-emptive treatment for cryptococcal antigen (CrAg) in blood in adults with CD4 <200 cells/µL reduces mortality. The World Health Organization does not recommend screening children <10 years due to a presumed low prevalence of CM. Nevertheless, CrAg testing is performed for all ages in South Africa in those with CD4 <100 cells/µL.

METHODS

Children (<18 years) with CD4 <100 cells/µL and a CrAg screening result were identified from National Health Laboratory Service records from 2017 to 2022 in South Africa. Fifteen healthcare facilities in Gauteng province were chosen for a convenience sample of CrAg-positive and matched CrAg-negative children to collect detailed clinical information.

RESULTS

Prevalence of cryptococcal antigenemia in South African children <18 years was 4.7% (1352/28,839) with a median age of 14 years (IQR 11-16). CrAg-positive prevalence in children <10 years was 3.5% (261/7440). Fifty-one CrAg-positive children were included for in-depth chart review. Twenty-four (24/49; 49%) CrAg-positive children had documented symptoms of meningitis at testing; 33% were diagnosed with CM. Forty-seven percent (8/17) of CrAg-positive children without documented symptoms developed their first CM episode in the subsequent 12 months. Five percent (1/19) of CrAg-positive children pre-emptively treated with fluconazole were subsequently diagnosed with CM, compared with 58% (7/12) of those without a documented prescription ( P = 0.002). The 6-month mortality for CrAg-positive children was 19% (7/36). No CrAg-negative children developed CM.

CONCLUSIONS

CrAg prevalence in children with CD4 <100 cells/µL is comparable to adults (4.7% and 5.8%, respectively). CrAg screening guidelines should be extended to include all children to improve outcomes.