Enfermedad renal poliquística autosómica recesiva: reporte de un caso / Autosomal recessive polycystic kidney disease: a case report

La enfermedad renal poliquística es una enfermedad genética que se caracteriza por dilataciones quísticas progresivas de los túbulos renales, presentándose de forma autosómica dominante o recesiva, con una incidencia de 1 en 1.000 y 1 en 20.000 nacidos vivos, respectivamente según series internacionales. La variedad autosómica recesiva puede ser letal en el período neonatal debido a insuficiencia respiratoria secundaria a hipoplasia pulmonar, y puede manifestarse durante la infancia con hipertensión arterial, talla baja y complicaciones secundarias a hipertensión portal. PRESENTACIÓN DEL CASO: paciente preescolar de 3 años 11 meses, con antecedente de restricción del crecimiento fetal y oligohidroamnios en período prenatal, presenta cuadro de decaimiento, palidez y dificultad alimentaria progresiva con vómitos posprandiales, destacando al examen físico un soplo cardíaco, hipertensión arterial, esplenomegalia, circulación colateral, además de talla baja. En exámenes destaca un hemograma con pancitopenia periférica, ecografía abdominal con hepatoesplenomegalia, hallazgos compatibles con enfermedad renal poliquística autosómica recesiva y fibrosis periportal, cintigrama renal con hipofunción renal bilateral, test de sangre oculta en deposiciones positivo, endoscopía digestiva alta convárices esofágicas pequeñas, radiografía de carpo con edad ósea retrasada y ecocardiografía con cardiomegalia. DISCUSIÓN: se requiere un alto índice de sospecha ante esta enfermedad poco frecuente, que cursa con hipertensión portal, siendo el recuento de plaquetas el mejor predictor de severidad. Dado que carece de tratamiento curativo y su historia natural es progresar haciala insuficiencia renal terminal, su tratamiento se enfoca en las complicaciones secundarias al daño hepático y renal...

Polycystic Kidney Disease is a genetic disorder characterized by progressive cystic dilations of the renal ducts, presenting as autosomal dominant or recessive forms with an incidence of 1 in 1.000 and 1 in 20.000 births, respectively, according to international series. The autosomal recessive variety can be lethal in the neonatal period due to respiratory failure secondary to pulmonary hypoplasia and can manifest during childhood with hypertension, short stature and complications of portal hypertension. CASE REPORT: 3 years and 11 months old preschoolar with antecedent of fetal growth restriction and oligohydramnios during prenatal period, and a historyof asthenia, pallor and progressive feeding difficulty with postprandial vomiting. Physical examination shows cardiac bruit, hypertension, splenomegaly, caput medusae and short stature. Laboratory tests with peripheral pancytopenia; abdominal ultrasonography showed hepatosplenomegaly, findings consistent with autosomal recessive polycystic kidney disease and periportalfibrosis; renal scintigraphy with bilateral kidney failure; a positive fecal occult blood test; an upper endoscopy that shows small esophageal varices; a hand radiography that shows bone age delayed and an echocardiography with cardiomegaly. DISCUSSION: This infrequent disease requires a high degree of suspicion by the clinician and presents with portal hypertension, with platelet count being the best predictor of severity. This condition has no cure and will progress to end-stage renal disease in any moment, so the aim is to minimize and treat renal and hepatic complications...

Síndrome hemolítico urémico en Chile: presentación clínica, evolución y factores pronósticos / Hemolytic-uremic syndrome in Chile: clinical features, evolution and prognostic factors

Background: Hemolytic-uremic syndrome (HUS) is characterized by acute renal failure, microangiopathic hemolytic anemia and thrombocytopenia. Aim: To describe the characteñstics ofpatients with the diagnosis ofHUS in Chile, and to identify the most reliable early predictors oímorbidity and moñality. Material and methods: The clinical records ofpatients with HUS aged less than 15 years, attended between January 1990 and December 2003 in 15 hospitals, were reviewed. Demographic, clinical, biochemical, hematological parameters, morbidity and mortality were analyzed. Results: A cohort of 587 patients aged 2 to 8 years, 48 percent males, was analyzed. Ninety two percent had diarrhea. At the moment of diagnosis, anuria was observed in 39 percent of the patients, hypertension in 45 percent and seizures in 17 percent. Forty two percent required renal replacement therapy (RRT) and perítoneal dialysis was used in the majoríty of cases (78 percent). The most frequently isolated etiological agentwas Escherichia coli. Mortality rate was 2.9 percent in the acute phase of the disease and there was a positive correlation between mortality and anuria, seizures, white blood cell count (WCC) >20.000/mm³ and requirements of renal replacement therapy (p <0.05). Twelve percent of patients evolved to chronic renal failure and the risk factors during the acute phase were the need for renal replacement therapy, anuria, WCC >20.000/mm³, seizures and hypertension. Conclusions: The present study emphasizes important clinical and epidemiological aspeets ofHUSin a Chilean pediatricpopulation.

Retiro precoz de esteroides en la inmunosupresión del trasplante renal pediátrico / Early steroid withdrawal in pediatric renal transplantation

Background: Cardiovascular risk, growth failure and the new immunosuppressive drugs, have encouraged steroid withdrawal or total avoidance with promising results in renal transplant (Tx) immunosuppression. Aim: To evaluate a new immunosuppressor protocol with early withdrawal of steroids in pediatric kidney transplant. Patients and methods: Prospective study in pediatric patients older than 1 year and low immunological risk. Group A (n =28): steroids in decreasing doses until day 7 post Tx, tacrolimus (FK) and micophenolate mofetil (MMF). Group B (n =28) control: steroids, cyclosporine and azathioprine or steroids, FK and MMF. In both groups the induction therapy included basiliximab. Anthropometric and biochemical variables (renal function, lipid profile, hematological, blood glucose and acid-base equilibrium), acute rejection and CMV infection, were evaluated. Mean values and variations for continuous variables were calculated at months 1, 6, 12 and 18. Results: Two children were withdrawn before month 2, one had an untreatable diarrhea and the second died due to Aspergillus septicemia. Mean values at months 1, 6, 12 and 18 for groups A and B: Creatinine clearence (ml/min): 85.4 vs 89; 79.9 vs 83; 89 vs 80; 79.8 vs 80.6 (p: ns); hematocrit ( percent): 28.8 vs 30.4; 31.7 vs 34.4; 34.4; 32.4 vs 34.8; 34.4 vs 35.5 (p: ns). Total cholesterol (mg/dl): 151 vs 206; 139 vs 174; 138 vs 186; 140 vs 180 (p <0.05). Mean delta height/age Z score at the first year: 0.5 vs 0.15; 0.7 vs 0.22; 0.97 vs 0.25 (p <0.05). Mean systolic blood pressure Z score: 0.9 vs 1.5; 0.5 vs 0.9; -0.3 vs 0.8; 0.1 vs 1.0 (p <0.05). The height/age Z score was significantly superior in patients without steroids. A normalization of growth patterns at month 18 was observed (< 0.05). Both groups presented a negative variation of creatinine clearance during the follow-up, but it was minor in the study group (p <0.05). Two acute rejections were found in each group, and no difference in CMV infections...