Urinary metabolic abnormalities in children with idiopathic hematuria.

BACKGROUND: Hematuria, either macroscopic or microscopic, is an incidental finding of multiple nephrologic or urologic disorders. Disturbances of urine inhibitors or promotors have been suggested as the potential causes of isolated idiopathic hematuria in children and its recurrence. Meanwhile, appropriate treatment of these risk factors might improve secondary asymptomatic or macroscopic hematuria. OBJECTIVES: The aim of this study was to identify contribution of urinary biochemical abnormalities in children with isolated idiopathic hematuria. METHODS: About 522 children with isolated hematuria were evaluated in a prospective cross-sectional study. Data such as clinical manifestations, family history, laboratory examinations, structural anomalies, and urine biochemistry were obtained. Patients with nephrolithiasis, nephrocalcinosis, tubulointerstitial disorder, genitourinary abnormality, urinary tract infection, and glomerular disorder were excluded from the study. Variables such as calcium, citrate, oxalate, phosphate, uric acid, cystine, and magnesium were measured in 24-h urine collection. In addition, serum levels of electrolytes, urea, creatinine, parathyroid hormone, and bicarbonate were identified. RESULTS: Mean age at diagnosis was 5.9 years, and females outnumbered males (2/1). Of those, 88.5% had microscopic hematuria, and 12.6% experienced episodes of gross hematuria. Abdominal pain was the most common clinical manifestations. Urinary tract infection occurred in 30% of cases. Totally, 94% of patients had single or multiple metabolic abnormalities in 24-h urine excretion including hypocitraturia, 60.7%; hypomagnesuria, 58.2%; hyperuricosuria, 35.8%; hypercalciuria, 33.7%; hyperoxaluria, 33.7%; and cystinuria, 0.76%, respectively. About 8% of cases had mixed urine metabolic disturbances. Most patients had mild hematuria (red blood cell <10/high power field (hpf)), and 18% had significant hematuria (>30/hpf), with no statistical correlation to urine metabolic abnormalities. About 80% of patients had a history of nephrolithiasis in their relatives. DISCUSSION: Decreased urinary inhibitor concentration followed by increased stimulator concentration were the most common abnormalities in patients with idiopathic hematuria. Accordingly, measurement of urinary biochemical concentration is highly recommended in children with isolated hematuria. In addition, investigating the therapeutic effect of potassium citrate supplements is highly recommended in these patients to prevent future stone formation and treatment of hematuria.

Effect of temperature changes on the occurrence of congenital hypothyroidism.

OBJECTIVES: To investigate an association between seasonal changes in temperature and the prevalence of congenital hypothyroidism (CH) in the Southwest of Iran. METHODS: A prospective two-year study conducted from March 2007 to March 2009 during the nationwide screening programme for CH in Ahvaz, the biggest city in southwest Iran. Blood samples were taken from almost all newborns by heel-stick and used in a thyroid-stimulating hormone (TSH)-enzyme-linked immunosorbent assay (ELISA). Serum thyroxine (T4) and TSH were measured if the ELISA-TSH was >5 mIU/L (suspicious cases). Infants were considered to have CH with T4 <6.0 µg/dL and TSH > 10 mIU/L, or with normal T4 values and persistent high TSH values for >2 months (subclinical hypothyroidism). Date of birth and sex were recorded. Detailed temperature data were obtained from the meteorological organization. The relationship between the monthly incidence of CH and the average monthly temperature was investigated. RESULTS: From 47,075 (50.92% male) newborns, 1131 were referred (recall rate = 2.4%) and 142 infants (51.4% male) were confirmed to have CH. The seasonal distribution of CH cases was 32.4% in the warm period and 67.6% in the cold period of the year (19%, 13.4%, 32.4% and 35.2% in spring, summer, fall and winter, respectively; P = 0.001). A statistical difference was seen between mid-summer (2.8%, warmest time) and early winter (15.5%, coldest time). The above-mentioned difference was the same for suspicious individuals (P < 0.001). The odds of being affected were increased by 4% for each fall of 1°C. CONCLUSION: The prevalence of CH has a significant negative correlation with the temperature in the tropical area of Iran.

Hemolytic uremic syndrome following Hemiscorpius lepturus (scorpion) sting.

Scorpion envenomations are a public health problem in many countries. Scorpions are second only to snakes in causing human fatalities from envenomation. Species of scorpions capable of inflicting fatal stings are living in North and South Africa, the Middle East, India, America, Trinidad, and Tobago. Hemiscorpius lepturus (from the Hemiscorpiidae family) is the most medically important scorpion in Iran which accounts for 92% of all hospitalized scorpion sting cases. The venom from H. lepturus is primarily a cytotoxic agent and has hemolytic, nephrotoxic, and to some extent, hepatotoxic activities. We found a combination of microangiopatic hemolytic anemia, thrombocytopenia, and acute renal failure in a seven year-old female child who was referred to us with a 12 h history of bloody urine following a H. lepturus sting. Her blood smear showed fragmented erythrocytes and burr cells, leading us to a diagnosis of hemolytic uremic syndrome (HUS). This report highlights the importance of acceptable prophylaxis and therapeutic protocols for HUS in these patients.