Tenofovir (TFV), a nucleoside reverse transcriptase inhibitor, is recommended in combination with other anti-retroviral drugs as first-line therapy for human immunodeficiency virus (HIV). Fanconi syndrome, acute kidney injury, and chronic kidney disease have been associated with tenofovir-associated toxicity. Clinical trial data have shown a lower rate of clinically significant renal events in those taking tenofovir alafenamide (TAF) compared with, tenofovir disoproxil fumarate (TDF). Studies have shown that TFV toxicity is more likely among African patients.

A 17-year-old G1P0 21.6 weeks and Congo refugee presented with fatigue, vomiting, and myalgia. Laboratory revealed normal creatinine, severe leukocytosis and hypokalemia, mild hypotension and hydronephrosis. Past history was significant for well controlled congenital HIV- 1 treated with bictegravir-emtricitabine-TAF (Biktarvy). Urinalysis revealed leukocytosis and empirical treatment with intravenous antibiotics for pyelonephritis and impending urosepsis initiated. At 22.5 weeks, patient was transferred to higher level of care for persistent severe hypokalemia despite repletion. On arrival to referral center imaging confirmed bilateral hydronephrosis (figure 1) that improved after foley catheter placement and position changes. Patient developed marked polyuria of 10 L/day and continued to have electrolytes imbalance and microcytic anemia rising concern medication-induced acute kidney injury due to Biktarvy, leading to Fanconi syndrome. But considering lower risk of renal toxicity with TAF and given patient's control on treatment, Biktarvy was continued. After five days of electrolyte repletion and tight fluid management the patient was discharged home with presumptive diagnosis of post-obstructive diuresis. Patient was scheduled for close follow up and continuing current ART regimen. At 25.2 weeks patient presented to local hospital completely dilated and underwent uncomplicated emergency primary cesarean section and delivered a viable female infant weighing 820g with 1minute Apgar 2 and 5- minute Apgar 7.

Outside of pregnancy, cessation of tenofovir is the main treatment option, often resulting in improvement of clinical manifestations of renal injury. However, in the setting of pregnancy when viral load is well-controlled on a medication, one must weigh the risk of vertical transmission to the fetus with changes to the antiretroviral regimen. Our case highlights clinical complexity in managing an adolescent-teenage pregnancy affected by congenital HIV.