Developmental regression as the presenting feature of late-diagnosed vertically acquired HIV infection in a child: 18-month follow-up.

We report a boy in mid-childhood with previously undiagnosed vertically acquired HIV who presented with progressive developmental regression, language impairment, gait disturbance and pyramidal signs. Investigations showed profound immunosuppression, high plasma and cerebrospinal fluid HIV RNA levels, diffuse white matter abnormalities and marked cerebral atrophy, supporting a diagnosis of HIV-associated encephalopathy. Combination antiretroviral therapy was initiated promptly, together with intensive multidisciplinary rehabilitation. During 18 months of follow-up, plasma HIV RNA became undetectable, immune function recovered and neurological, cognitive, language and functional outcomes improved. This case documents an uncommon paediatric neurodevelopmental manifestation of HIV and highlights the importance of considering HIV in children with unexplained developmental regression, as well as the contribution of sustained rehabilitation to recovery alongside virological control.