Nephropathic cystinosis presenting with uveitis: Report of a “Can't See, Can't Pee” situation

Nephropathic cystinosis is a rare autosomal recessive lysosomal disease characterized by accumulation of pathognomonic cystine crystals in renal and other tissues of the body. Cystinosis is caused by mutant cystinosin, the cystine transport protein located in lysosomal membranes, leading to systemic deposits of cystine and resultant end organ damage. Cystinosis is rarer in Asians than Caucasians with only a handful of cases reported from India to date. Due to its extreme rarity and clinically insidious presentation in contrast to the infantile form, the diagnosis of juvenile nephropathic cystinosis is frequently delayed or overlooked. Moreover, routine processing and sectioning of paraffin embedded tissues dissolves cystine crystals, making it difficult to diagnose this condition on light microscopic examination alone, mandating electron microscopic (EM) analysis of renal biopsies for an accurate diagnosis of this condition. We describe a case of juvenile nephropathic cystinosis presenting with uveitis and photophobia in a 17-year-old Indian male, diagnosed after EM examination of the patient's renal biopsy for evaluation of nephrotic syndrome. While highlighting the diagnostic utility of EM, we describe a few histopathologic clues which can prompt inclusion of EM analysis of renal biopsies in this setting.

Renal Tubular Acidosis Presenting as Nephrogenic Diabetes Insipidus

Background: Nephrogenic diabetes insipidus (DI) can be primary or secondary to variouscauses. Case Characteristics: One child with Fanconi syndrome with proximal renaltubular acidosis (RTA) due to nephropathic cystinosis, and other with Distal RTA withhearing loss. Observation: Both cases showed features of nephrogenic DI, which resolvedafter treating the primary pathology. Message: Renal Tubular acidosis may causenephrogenic DI.

Cristales oportunos: cistinosis nefropática. Reporte de caso / Timely cristals: nephropathic cystinosis. Case report

Objetivo: Describir el caso clínico de un paciente con Cistinosis Nefropática diagnosticado a muy temprana edad. Método: Reporte de caso. Resultados: Se reporta el caso de una paciente de 7 meses de edad, quien consulta con poliuria, piolidipsia, glucosuria y bajo peso para la edad. De acuerdo a protocolos de evaluación interdisciplinaria establecidos con el servicio de Pediatría se logra evidenciar hallazgos oculares que orientan al diagnóstico final de la paciente. Conclusión: La Cistinosis es una enfermedad rara, cursa con manifestaciones oculares que podrían orientar un diagnóstico temprano e incluso predecir la severidad de la enfermedad y brindar la posibilidad de un tratamiento temprano. Es importante establecer protocolos interdisciplinarios, de apoyo diagnóstico, ante la sospecha de enfermedades sistémicas con posible compromiso ocular, en lugar de desistir ante la dificultad para valorar a los niños en la consulta de oftalmología, sobre todo en aquellos menores de un año. Se demuestra este caso con fines académicos teniendo en cuenta la baja incidencia de la enfermedad, pero también para destacar la importancia de contar con protocolos de atención interdisciplinaria ante la sospecha de enfermedades metabólicas en todas las edades.

Purpose: To describe a case of an infant with Nephropathic Cystinosis and the ocular fi ndings that leads to the diagnosis. Method: Case report. Results: Th is report describe a prompt and accurate diagnosis of a 7 months old patient, who consults with polyuria, piolidipsia, glucosuria and low weight. According to interdisciplinary evaluation protocols previusly established with Pediatrics services, it was possible to demonstrate ocular fi ndings of the disease, guiding the physician to the fi nal diagnosis. Conclusion: Cystinosis is a rare disease, its clinical presentation has ocular manifestations that could guide diagnosis and even predict its severity, off ering the possibility of an early treatment. When one suspect a systemic disease, It is important to establish interdisciplinary protocol, instead of surrendering to the challenge of an ophthalmological examination of an infant. We choose this case due to its low incidence, but also to highlight the importance of having interdisciplinary care protocols when a metabolic disease is suspected.