Resumo A hiperoxalúria primária (HP) é um distúrbio genético muito raro, caracterizado por deficiência total ou parcial das enzimas relacionadas ao metabolismo do glioxilato, superprodução de oxalato de cálcio que se deposita em vários órgãos (principalmente os rins) resultando em litíase recorrente, nefrocalcinose e doença renal terminal (DRT). Nos pacientes com DRT que recebem transplante renal, a doença apresenta recidiva em 100% dos casos, com perda do enxerto nos primeiros cinco anos após o transplante num elevado percentual de pacientes. Três distúrbios moleculares foram descritos na HP: mutação dos genes da alanina-glioxilato aminotransferase (AGXT), glioxilato redutase/hidroxipiruvato redutase (GRHPR) e 4-OH-2-oxoglutarato aldolase (HOGA1). Apresentamos dois casos de pacientes com histórico de litíase renal diagnosticados com hiperoxalúria primária no período pós-transplante, manifestada na forma de perda precoce do enxerto com evidências de cristais de oxalato de cálcio na biópsia renal, hiperoxalúria, hiperoxalemia e testes genéticos compatíveis. Os pacientes foram tratados com abordagem nutricional, líquidos orais em abundância, piridoxina, hidroclorotiazida e citrato de potássio. Contudo, os pacientes apresentaram deterioração lenta e gradual da função do enxerto e evoluíram para doença renal terminal.

Abstract Primary hyperoxaluria (PH) is a very rare genetic disorder; it is characterized by total or partial deficiency of the enzymes related to the metabolism of glyoxylate, with an overproduction of calcium oxalate that is deposited in different organs, mainly the kidney, leading to recurrent lithiasis, nephrocalcinosis and end stage renal disease (ESRD). In patients with ESRD that receive kidney transplantation alone, the disease has a relapse of 100%, with graft loss in a high percentage of patients in the first 5 years of transplantation. Three molecular disorders have been described in PH: mutation of the gene alanin glioxalate aminotransferase (AGXT); glyoxalate reductase/hydroxy pyruvate reductase (GRHPR) and 4-OH-2-oxoglutarate aldolase (HOGA1). We present two cases of patients with a history of renal lithiasis who were diagnosed with primary hyperoxaluria in the post-transplant period, manifested by early graft failure, with evidence of calcium oxalate crystals in renal biopsy, hyperoxaluria, hyperoxalemia, and genetic test compatible; they were managed with proper diet, abundant oral liquids, pyridoxine, hydrochlorothiazide and potassium citrate; however, they had slow but progressive deterioration of their grafts function until they reached end-stage chronic renal disease.

RESUMEN La enfermedad renal asociada a cadenas ligeras es frecuente en el contexto de las gammapatías monoclonales, afecta los glomérulos o los túbulos renales, y su causa más común es el mieloma múltiple. Puede desarrollarse después de un trasplante renal por recurrencia de un mieloma múltiple ya existente, o puede ser de diagnóstico nuevo y presentarse con deterioro de la función renal y proteinuria. Siempre se requiere una biopsia renal para confirmar el diagnóstico.

ABSTRACT Light chain-associated kidney compromise is frequent in patients with monoclonal gammopathies; it affects the glomeruli or the tubules, and its most common cause is multiple myeloma. It may develop after a kidney transplant due to recurrence of a preexisting multiple myeloma or it can be a de novo disease manifesting as graft dysfunction and proteinuria. A kidney biopsy is always necessary to confirm the diagnosis.

Resumen La toxoplasmosis posterior al trasplante renal es una condición infrecuente, pero asociada con alta morbilidad y mortalidad. Generalmente ocurre en los primeros tres meses cuando la inmunosupresión es mayor, siendo más común la presentación con encefalitis y neumonitis. El compromiso del tracto gastrointestinal es inusual y con síntomas inespecíficos. Su diagnóstico es un reto pues no siempre existe seroconversión en estadios tempranos de la infección o no hay evidencia histológica del parásito; es aquí donde la biología molecular y la historia clínica pueden resultar útiles para el diagnóstico oportuno que favorezca un buen desenlace. Describimos el caso de un paciente con síntomas generales, náuseas y emesis en el periodo postrasplante renal temprano atribuidos primero a reactivación de citomegalovirus con diagnóstico posterior de gastritis por Toxoplasma gondii. Recibió tratamiento con trimetoprim sulfametoxazol por seis semanas con resolución completa de los síntomas. (Acta Med Colomb 2016; 40: 266-268).

Abstract Toxoplasmosis following renal transplantation is an uncommon condition, but is associated with high morbidity and mortality. It usually occurs in the first three months when immunosuppression is greater, being more common the presentation with encephalitis and pneumonitis. The involvement of the gastrointestinal tract is unusual and with nonspecific symptoms. Its diagnosis is a challenge because there is not always seroconversion in the early stages of infection or there is no histological evidence of the parasite; it is here that molecular biology and clinical history can be useful for a timely diagnosis that may favor a good outcome. The case of a patient with general symptoms, nausea and emesis in the early renal transplant period attributed initially to reactivation of cytomegalovirus with subsequent diagnosis of gastritis by Toxoplasma gondii, is described. He received treatment with trimethoprim sulfamethoxazole for six weeks with complete resolution of symptoms. (Acta Med Colomb 2016; 40: 266-268).

Resumen El síndrome de hiperestimulación ovárica es una complicación frecuente que se puede presentar en pacientes que reciben tratamientos de inducción de la ovulación y como consecuencia pueden desarrollar un síndrome edematoso grave con falla de uno o varios órganos; presentamos el caso de una paciente con falla renal aguda asociada a síndrome de hiperestimulación ovárica. (Acta Med Colomb 2016; 41:58-61).

Abstract Ovarian hyperstimulation syndrome is a common complication that can occur in patients receiving treatment for ovulation induction and as a consequence may develop a severe edematous syndrome with failure of one or more organs; the case of a patient with acute renal failure associated with ovarian hyperstimulation syndrome is presented. (Acta Med Colomb 2016; 41:58-61).