Hypophosphatemic osteomalacia associated with tenofovir: a multidisciplinary approach is required.

Abstract

Tenofovir is widely used as first-line treatment of HIV infection, although its use is sometimes complicated by a reversible proximal renal tubulopathy.We report the case of a 45-year-old woman with chronic HIV infection and personality disorder, who after 12 months of tenofovir, complained of fatigue, diffuse bone pain and gait disturbances. The elevated level of alkaline phosphatase, hypophosphatemia and inappropriate phosphaturia suggested the diagnosis of hypophosphatemic osteomalacia secondary to proximal renal tubulopathy. A dual-energy x-ray absorptiometry showed a bone mineral density below the expected range for age (lumbar spine Z-score −3.3, femoral neck Z-score −2.1). A whole body 99mTc-methylene diphosphonate bone scan showed multiple areas of increased focal activity in the lumbar and thoracic spine and in sacroiliac and hip joints consistent with pseudofractures. Two months after tenofovir discontinuation and administration of vitamin D and phosphate, osteomalacia-related symptoms disappeared. Eleven months later, bone and mineral metabolism data were normal and bone scintigraphy did not show any pathological findings.This report highlights the importance of considering the diagnosis of osteomalacia in patients treated with tenofovir and emphasizes the need for monitoring alkaline phosphatase, blood and urinary phosphate and creatinine, especially in patients with risk factors for bone disease.

Tenofovir monotherapy for hepatitis B after 1 year does not produce renal dysfunction, but is associated with hyperparathyroidism not related to vitamin D

“…Several studies have associated the use of TDF in HIVinfected patients with renal dysfunction, renal phosphate wasting, bone pain, and osteomalacia [6][7][8]. Renal proximal tubular syndrome, including glycosuria and phosphaturia, as well as a specific type of a newly recognized renal tubulopathy with mitochondrial injury has also been described in HIV-infected individuals on TDF therapy [9].…”

68Ga DOTATATE PET/CT is an Accurate Imaging Modality in the Detection of Culprit Tumors Causing Osteomalacia

“…However, a patient having both osteomalacia and hypophosphatemia still does not necessarily have TIO because hypophosphatemic osteomalacia can still have other etiologies. [14][15][16] Identifying the culprit tumor by imaging provides opportunity of surgical resection and chance of final, confirmed diagnosis.…”

Patrón gammagráfico “superscan” en la osteomalacia hipofosfatémica asociada a Tenofovir en un paciente con infección por VIH

“…Los patrones gammagráficos más frecuentemente en los casos publicados en la literatura son aquellos con captaciones compatibles con fracturas por insuficiencia o pseudofracturas [2,3,9]. Sin embargo, en 3 de ellos se encontró un aumento generalizado de la incorporación del trazador en todo el esqueleto con ausencia o muy débil visualización de las siluetas renales, patrón conocido como "superscan" [4,5,6,19].…”

“…Entre estos fármacos se encuentra el tenofovir disoproxil fumarato (TDF), un análogo de nucleó-tido inhibidor de la transcriptasa inversa ampliamente utilizado debido a su perfil de seguridad y tolerancia. Sin embargo, ha sido asociado con nefrotoxicidad, disminución de la densidad mineral ósea y osteomalacia hipofosfatémica (OMH) [2,3]. Presentamos el caso de un paciente con infección por VIH que desarrolló un cuadro de OMH durante el tratamiento con TDF que mostraba un patrón de "superscan" en la gammagrafía ósea, el cual ha sido descrito con poca frecuencia en este tipo de pacientes [4,5,6].…”