Nefrologia Pediátrica
Permanent URI for this community
Browse
Browsing Nefrologia Pediátrica by Author "Abranches, M"
Now showing 1 - 10 of 12
Results Per Page
Sort Options
- Acidose Tubular Renal Distal e Surdez Neurossensorial com Mutação no Gene ATP6V1B1Publication . Periquito, I; Casimiro, A; Santo, C; D’Elia, C; Abranches, M; Castro, IA acidose tubular renal distal é uma doença rara, caracterizada pela incapacidade na acidificação da urina, condicionando acidose metabólica hiperclorémica, hipocaliémia, hipercalciúria e nefrocalcinose, o que poderá causar atraso de crescimento, alteração do metabolismo ósseo e insuficiência renal crónica. A acidose tubular renal distal associada a surdez neurossensorial é uma doença de herança autossómica recessiva, causada por mutações do gene que codifica a subunidade B1 da H+ -ATPase (ATP6V1B1). Os autores relatam os casos de duas irmãs que apresentaram má progressão ponderal, alterações iónicas, do equilíbrio ácido base e surdez neurossensorial. Foi detectada em ambas as crianças a mutação homozigótica no gene ATP6V1B1. Com estes dois casos pretende -se destacar a importância de um diagnóstico precoce nesta patologia rara.
- Coexistence of Pheochromocytoma and Renal Artery Stenosis in a Pediatric Patient with HypertensionPublication . Serras, I; Baeta Baptista, R; Francisco, T; Casimiro, A; Lito, D; Alves, R; Abranches, MPheochromocytoma and renal artery stenosis are surgically treatable causes of hypertension. Although rare, the coexistence of pheochromocytoma and renal artery stenosis has been described in case reports. Common pathophysiological mechanisms other than extrinsic compression may be involved in this association, such as catecholamine-induced vasospasm. The early recognition of the association of pheochromocytoma with renal artery stenosis is essential for appropriate treatment planning. We present the case of a previously healthy tenyear- old boy who presented with hypertensive encephalopathy, tachycardia and diaphoresis. Hypertension was found to be secondary to a catecholamine-producing tumor associated with coexisting renal artery stenosis. Hypertension resolved a few months after successful pheochromocytoma excision, without renal artery revascularization.
- Diagnóstico Pré-Natal das Anomalias do Tracto Urinário: Dez Anos de ExperiênciaPublication . Batista, J; Abranches, M; Silva, A; Ferra de Sousa, JIntrodução: As anomalias do tracto urinário são detectadas com uma frequência cada vez maior devido à sistematização da vigilância ecográfica durante a gravidez aliada à sofisticação técnica e à experiência dos ecografistas. Objectivo: Analisar os principais diagnósticos pós-natais investigados na sequência do estudo evolutivo prolongado das uropatias fetais seguidas no ambulatório da nefrologia pediátrica do Hospital de Dona Estefânia. Doentes e Métodos: Estudo retrospectivo dos 392 casos de uropatia fetal observados num período de dez anos e submetidos ao protocolo de investigação em uso na unidade. Resultados: O estudo inclui 362 casos; excluímos 30 processos que não completaram a investigação. A relação sexo masculino: feminino foi de 2: 1. O diagnóstico pré-natal foi realizado em média às 28.9 semanas e a idade média de admissão foi de 68 dias. No estudo evolutivo pós-natal verificou-se a formulação de um diagnóstico definitivo em 349 (96.4%) das crianças. Em 109 crianças (30%) a anomalia fetal foi transitória. Em 75 (20.7%) a dilatação era funcional. Confirmou-se a existência de uropatia em 165/362 crianças: refluxo vesico-ureteral 70/165 (42.4%), displasia multiquística 21%, síndroma da junção pielo-ureteral 16.4%, entre os principais. Nenhum caso evoluiu para insuficiência renal e há a registar, apenas, um caso de hipertensão arterial por poliquistose renal. Conclusão: A planificação da investigação pós-natal reveste-se ainda de alguma controvérsia e continua a evoluir principalmente no grupo das anomalias unilaterais e assintomáticas.
- Diagnóstico Pré-Natal de Uropatia: Importância do Desenvolvimento Embriológico RenalPublication . Serrão, AP; Abranches, M; Ferra de Sousa, JAs uropatias malformativas constituem a principalcausa de anomalia neonatal nao letal. Estas anomalias do desenvolvimento devem ser interpretadas com base no conhecimento da morbilidade e, em alguns casos, a mortalidade associada a este tipo de patologia 1,2. As malformações congénitas devem ser pensadas com base no conhecimento da dinâmica do normal desenvolvimento embrionário e dos múltiplos factores reguladores intervenientes, so assim será possivel estabelecer estratégias eficazes de investigação e terapêutica.
- Fanconi Syndrome after Ifosfamide ExposurePublication . Madeira Gomes, S; Francisco, T; Serrão, AP; Abranches, Mntroduction: Ifosfamide is an antineoplastic drug frequently used in the treatment of pediatric malignancies. However it is responsible for nephrotoxicity in up to 30% of patients, which can be manifested from asymptomatic tubulopathy to overt renal failure. We report a case of a patient who developed Fancony syndrome after exposure to ifosfamide. Clinical Case: A two-year-old caucasian boy was diagnosed with stage IV Burkitt lymphoma with hepatic and renal involvement without central nervous system (CNS) invasion. Baseline evaluation showed GFR of 60 mL/min per 1.73 m2 (Shwartz formula, k=0.143). He underwent five cycles of chemotherapy involving cyclophosphamide, vincristine, prednisolone, doxorubicin, methotrexate and cytarabine. The patient was in remission but three months later relapsed with evidence of involvement of the liver and kidneys on CT. Another course of chemotherapy was initiated with ifosfamide, carboplatin, etoposide, rituximab (R-ICE) and intratecal administration of methotrexate and aracitabine. After five cycles of R-ICE, the patient had a bone marrow transplant. According to protocol, busulfan, cyclophosphamide, tacrolimus, methotrexate, fluconazole and acyclovir were administered. No immediate complications were registered. Four months after transplant, the patient showed significant downward growth percentile crossing and urinalysis suggested tubulopathy. Upon nephrologist referral, laboratory investigations showed GFR 60 mL/min per 1.73 m2, metabolic acidosis, hypouricemia, hypokalemia, hypophosphatemia, glycosuria, proteinuria, high FEUa and FEK, and low GFR of phosphorus. Fancony syndrome was diagnosed and adequate supplementation was initiated. After literature review the most probable causing agent was ifosfamide. After adequate treatment patient’s general condition improved with slow percentile recovery. Conclusions: Nephrotoxicity secondary to chemotherapy is a major cause of morbidity in pediatric cancer survivors. Our case represents a rare situation with unspecific clinical signs. Clinicians must be alert to the necessity of close monitoring to identify renal toxicity as early as possible and allow adequate supplementation, which is crucial in preventing side effects.
- Hypophosphatemic Rickets: A New MutationPublication . Maio, P; Rocha, S; Mano, L; Francisco, T; Sousa, H; Freixo, J; Abranches, MIntroduction: Phosphopenic rickets is characterized by hypophosphatemia with hyperphosphaturia, normal calcemia and normal or mildly elevated PTH. This pathology may be caused by mutations in PHEX gene (phosphate regulating endopeptidase homolog X-linked). We present a clinical report of a girl with phosphopenic rickets, as consequence of a new mutation of PHEX gene. Clinical Case: We present a 4-year-old female, with unremarkable family history, who presented with failure to thrive since the first year of life (height at the 5th centile, and with the age of four below 5th centile). Blood tests showed hypophosphatemia (2.4 mg/dL), elevated alkaline phosphatase (495 U/L), normal calcemia, mildly elevated PTH (97.2 pg/mL; RR <68.3) and normal levels of 25(OH)D and 1.25(OH)D vitamins. The radiological study showed bone deformity of the radius and femur. Diagnosis of hypophosphatemic rickets was made and she was medicated with phosphorus and calcitriol. Currently, the patient has no clinical or radiographic signs of rickets, osseous age is according to real age and there was a considerable increase in growth rate (between 25th and 50th centiles). Renal ultrasound shows incipient signs of nephrocalcinosis since she was 9-year-old. The genetic study detected a heterozigous mutation of the PHEX gene: variant c.767_768del (p.Thr256Serfs*7). This variant is not described in the literature or databases. However, since it introduces a premature stop codon that can produce a truncated protein, this is very likely a pathogenic variant. The parent’s genetic study is still in progress. Conclusions: Presently more than 200 mutations in the PHEX gene have been found to cause hypophosphatemic rickets. We describe a new mutation of this gene. Knowledge about new mutations can improve patient’s outcome.
- Influenza B-Associated Atypical Hemolytic Uremic SyndromePublication . Mano, L; Rocha, S; Maio, P; Francisco, T; Pereira, G; Gomes, S; Santos, R; Serrão, AP; Abranches, MIntroduction: Influenza A infections have been described to cause secondary hemolytic uremic syndrome and to trigger atypical hemolytic uremic syndrome (aHUS) in individuals with an underlying genetic complement dysregulation. To date, Influenza B has only been reported to trigger aHUS in 2 patients. In 61% of aHUS cases, mutations are found in H, B and I factors, membrane cofactor protein (MCP), C3 and thrombomodulin. MCP (CD46) mutations account for 10-15% of cases. Clinical Case: A 13-year-old boy was transferred to a terciary pediatric centre with acute renal lesion in the context of HUS. Evidence was found for Influenza B infection and results for other etiologic agents were negative. He was treated with Oseltamivir for 5 days. Etiologic study revealed decreased C ́3 (0,81 g/L), normal C ́4 (0,27 g/L) and all antibodies were negative: anti-Beta2 GP1 IgG / IgM, anti-cardiolipine IgG / IgM, anti-neutrophil-citoplasm-PR3 and MPO. Alternate complement pathway study (AH 50) were 112 % of normal value (reference value >70%) and ADAMTS 13 activity were 0.79 (values above 0.67 may be found in aSHU as well as other microangiopathic trombopathies). Molecular study of complement including 11 genes (CFH, CD46 (MCP), CFI, C3, THBD, CFB,CFHR5, CFHR1 CFHR3, CFHR4, DGKE) found a pathogenic heterozygotic missense variant on CD46 (MCP) gene, c.554A>G, p.Asp185Gly, associated with aHUS. Conclusions: aHUS patients should be screened for all known disease-associated genes. Screening should not be stopped after finding a mutation to avoid missing other genetic susceptibility factors influencing disease phenotype, particularly in patients with MCP or CFI mutations, because they have a higher probability of also carrying mutation in another gene than patients with CFHor C3 mutations. Influenza B is a trigger for aHUS and might be underreported as such. Influenza vaccination may protect patients at risk.
- Nephrolithiasis in a Portuguese Pediatric PopulationPublication . Andrade, J; Bota, S; Francisco, T; Santos, R; Neto, G; Abranches, MIntroduction and Aims: Nephrolithiasis incidence in children has increased considerably. It is associated with substantial morbidity, recurrence and increased adulthood cardiovascular risk and chronic kidney disease. A thorough investigation is essential, as rare forms of urolithiasis have increased risk of renal failure. We aim to determine the epidemiology and outcomes of a pediatric population with nephrolithiasis presented in a nephrology unit of a tertiary centre. Methods: Retrospective study of the records of all children (<18 years) with nephrolithiasis diagnosis between 2008‑17. Clinical features, etiology, recurrence, treatment, and outcomes were evaluated and compared throughout the study period through two equal periods (2008‑12 versus 2013‑17). Results: We identified 80 cases: isolated nephrolithiasis (86%) and associated with nephrocalcinosis (14%). Mean follow‑up was 36 months (14–120). Median age at presentation was 8.6 years [3 months – 17 years]: 21% < 2 years‑old and 46% ≥ 10 years. The annual ratio of referrals for nephrolithiasis increased on average 1.2% per year [0.3‑11.8%]. Multiple etiological factors were present in 34%. A metabolic abnormality was identified in 54%: hypocitraturia (34%), hypercalcuria (24%), hyperoxaluria (15%), hyperuricosuria (15%) and cystinuria (1%), without age predominance (p=0.2). Urinary tract infection (24%) was the next most significant etiology and was more frequent below 2 years of age (p=0.001) and associated with struvite calculi (p=0.033). Median age at diagnosis was significantly lower in the study’s first half (5 vs 10 years; p=0.019) and an infectious etiology was more frequent (p=0.043). In a logistic‑regression analysis, a family history of nephrolithiasis was associated with a metabolic cause (p<0.01). Sixty‑three percent became stone free and 24% had recurrence. Discussion: Nephrolithiasis new referrals gradually increased throughout the study period. The most common etiology was metabolic, which is usually responsible for nephrolithiasis appearance and its recurrence, emphasizing the need for a complete evaluation.
- Primary Hyperoxaluria type 1 – Two Case ReportsPublication . Ganhão, I; Borges, C; Amorim, M; Braga da Cruz, M; Nobre, S; Francisco, T; Cardoso, D; Abranches, MPrimary hyperoxaluria type 1 is a rare autosomal recessive inherited disease, caused by mutations in AGXT gene, with an estimated incidence of 1:100.000 live births per year in Europe. Over 50% present with end stage renal disease at diagnosis. Case reports: The first case is a 14‑year‑old boy, second child to consanguineous parents, with history of recurrent lithiasis and ureteral dilatation starting 5 years before. Urine/stone analysis revealed calcium oxalate monohydrate crystals and markedly elevated urine oxalate excretion. Genetic tests confirmed a mutation in AGXT gene, c.1151T>C, in homozygosity. Two years after, nephrocalcinosis was identified and glomerular filtration rate gradually declined. Oxalate deposition in solid organs was excluded and successful orthotopic liver transplantation was performed, with stabilization of glomerular filtration rate. The second case is a 16‑year‑old girl, with recurrent episodes of renal colic. At diagnosis, she had obstructive hydronephrosis, multiple kidney stones and an estimated glomerular filtration of 42.1mL/min/1.73m2. Metabolic study showed hypocitraturia and hyperoxaluria. With dietetic measures and irregular treatment, urine oxalate excretion remained high but renal function improved. Genetic tests confirmed the presence of two pathologic variants in AGXT gene: c.731T>C and c.1151T>C in compound heterozygous. Conclusions: Recurrent urolithiasis and nephrocalcinosis in children along with family history/consanguinity should raise the suspicion of Primary Hyperoxaluria type 1. Conservative treatment may increase renal survival. Effects of systemic oxalosis must be screened when glomerular filtration rate declines below 30‑50mL/ min/1.73m2, and sequential or combined liver and kidney transplantation should be considered.
- Sarcoma de Kaposi Iatrogénico con Afectación Cutánea ExclusivaPublication . Maia, R; Abranches, M; Serrão, AP; Castro, I