[Oculocardiac reflex associated with orbital floor fracture; the value of a reliable patient history]. / Oculo-cardiale reflex bij een orbitabodemfractuur; het belang van een betrouwbare anamneses.

BACKGROUND: The oculocardiac reflex presents when traction is applied to ocular muscles or on compression of the eyeball in the orbit. It is a vasovagal reaction that may be accompanied by bradycardia, nausea and vomiting. CASE DESCRIPTION: A 6-year-old boy presented with vomiting and acute pain in his right eye, but no history of trauma. On physical examination we found no abnormalities other than bradycardia. Ocular examination showed an elevation restriction and slight depression restriction as well as ptosis of the affected eye. A cerebral MRI scan showed a blow-out fracture of the orbital floor with herniation of the inferior rectus muscle. The oculocardiac reflex explained the bradycardia and vomiting. Later, the boy told us that he had in fact hit his eye with his own knee. CONCLUSION: When patients present with acute pain in the eye and vasovagal symptoms, the oculocardiac reflex that can accompany a fracture of the orbital floor should be considered. The early recognition and treatment of this fracture are necessary to prevent permanent motility restrictions of the eye. A patient's history is not always reliable and should not limit a differential diagnosis.

Neurocognitive functioning in school-aged cystinosis patients.

INTRODUCTION: Cystinosis is an autosomal recessive disorder leading to intralysosomal cystine accumulation in various tissues. It causes renal Fanconi syndrome and end stage renal failure around the age of 10 years if not treated with cysteamine. Children with cystinosis seem to have a normal intelligence but frequently show learning difficulties. These problems may be due to specific neurocognitive deficits rather than impaired renal function. Whether cysteamine treatment can improve cognitive functioning of cystinosis patients is thus far unknown. We aim to analyze neurocognitive functioning of school-aged cystinosis patients treated with cysteamine in order to identify specific deficits that can lead to learning difficulties. PATIENTS AND METHODS: Fourteen Dutch and Belgian school-aged cystinosis patients were included. Glomerular filtration rate was estimated using the Schwartz formula. Children were tested for general intelligence, visual-motor integration, inhibition, interference, sustained attention, accuracy, planning, visual memory, processing speed, motor planning, fluency and speed, and behavioural and emotional functioning using standardized methods. RESULTS: Glomerular filtration rate ranged from 22 to 120 ml min(-1) 1.73 m(-2). Median full-scale intelligence was below the average of a normal population (87, range 60-132), with a discrepancy between verbal (median 95, range 60-125) and performance (median 87, range 65-130) intelligence. Over 50% of the patients scored poorly on visual-motor integration, sustained attention, visual memory, planning, or motor speed. The other tested areas showed no differences between patients' and normal values. CONCLUSION: Neurocognitive diagnostics are indicated in cystinosis patients. Early recognition of specific deficits and supervision from special education services might reduce learning difficulties and improve school careers.

Partial hypoxanthine-guanine phosphoribosyl transferase deficiency without elevated urinary hypoxanthine excretion.

Partial hypoxanthine-guanine phosphoribosyl transferase (HGPRT) deficiency, also known as the Kelley-Seegmiller syndrome, can give rise to a wide range of neurological symptoms, and renal insufficiency. Biochemically, it is characterized by high uric acid concentrations in blood, high uric acid and hypoxanthine excretion in urine, and decreased activity of hypoxanthine-guanine phosphoribosyl transferase activity (HGPRT). However, normal uric acid concentrations in blood and uric acid excretions in urine have been reported. Here, a boy is presented with normal development and suffering from recurrent attacks of acute renal failure with slightly to clearly increased urinary uric acid excretion. Between these attacks, episodes of elevated urinary excretion of uric acid were observed with normal blood concentrations of uric acid and normal urinary excretion of hypoxanthine. HGPRT activity in erythrocytes, leukocytes, and fibroblasts was found to be strongly decreased. This case shows that not only normal blood uric acid but also normal urinary hypoxanthine concentrations do not exclude the diagnosis of partial HGPRT deficiency.

[From gene to disease; hypophosphataemic rickets and the PHEX gene]. / Van gen naar ziekte; hypofosfatemische rachitis en het PHEX-gen.

X-linked hypophosphataemic rickets is associated with mutations in the PHEX gene on the short arm of the X chromosome, encoding a membrane-bound endoprotease which is predominantly expressed in osteoblasts. Defective PHEX function leaves phosphaturic peptides such as FGF23 uncleaved, enabling these peptides, known as phosphatonins, to fully exert their phosphaturic potential in the proximal tubule of the kidney. An autosomally inherited form of hypophosphataemic rickets is caused by mutations in the proteolytic processing site of FGF23 itself, while in tumour-induced osteomalacia overproduction of FGF23 and possibly other phosphatonins causes the processing capacity to be exceeded, resulting in phosphaturic hypophosphataemia and osteomalacia.

Malpuech syndrome: three patients and a review.

We describe three patients with Malpuech syndrome from two families. Previously, 10 patients from 6 families have been reported. Consanguinity in two families suggests autosomal recessive inheritance. Growth retardation, mental retardation, cleft lip, and/or palate, hypertelorism, urogenital abnormalities, and caudal appendage are the key features. Although the spectrum of the features in the reported patients is variable, we do think this syndrome represents a distinct entity. Chromosomal anomalies should be carefully searched for. We discuss differential diagnosis and possible candidate genes and propose diagnostic criteria for Malpuech syndrome.

Renal function in tyrosinaemia type I after liver transplantation: a long-term follow-up.

Hereditary tyrosinaemia type I is an autosomal recessive inborn error of tyrosine catabolism caused by a deficiency of the enzyme fumarylacetoacetase that results in liver failure, hepatocellular carcinoma, renal tubular dysfunction and acute intermittent porphyria. When treated with liver transplantation, tyrosinaemia type I was considered to be cured. Some years after the first liver transplantations in these patients, some reports focused on the renal function after transplantation. These reports showed that urinary succinylacetone excretion remained but that tubular function normalized. In this report we discuss the long-term renal follow-up (mean follow-up time 11 years, range 7-14 years) after liver transplantation in 9 patients with tyrosinaemia type I treated by liver transplantation in our centre. An evaluation was made of renal function and succinylacetone excretion in urine. In all patients we found a persistent excretion of succinylacetone in the urine. With respect to the glomerular function, we can conclude that there is no clear change in GFR. At the same time, tubulopathy persisted in some patients. We consider that excretion of metabolites such as succinylacetone will be an important contributing factor to tubular dysfunction after liver transplantation in patients with tyrosinaemia type I. Therefore, notwithstanding the major effect of liver transplantation on tyrosine metabolism, renal tubular dysfunction remains at risk and needs careful monitoring. Progressive tubular dysfunction can cause glomerular damage. The use of low-dose NTBC might be considered after liver transplantation in case of tubulopathy to prevent progression of tubular and glomerular dysfunction.

[IgA-nephropathy in childhood]. / IgA-nefropathie op de kinderleeftijd.

IgA nephropathy or M. Berger is regularly diagnosed in childhood. A kidney biopsy is necessary to verify the diagnosis, by demonstrating deposition of IgA in the glomerular mesangium. The kidney biopsy is performed in cases of recurrent macroscopic haematuria or persistence of microscopic haematuria, with or without proteinuria. The prognosis and factors influencing the prognosis in childhood IgA nephropathy are uncertain. In a mainly retrospective study we tried to find correlations between clinical and histological findings and the outcome after a mean follow up period of 7.36 years in 56 patients. In this study with its restrictions it was impossible to find correlations between histological parameters and outcome on one side and between sex, hypertension, macroscopic c.q. microscopic haematuria, proteinuria and outcome on the other hand.

[Clinico-pathological correlations in IgA-nephropathy]. / Klinische-pathologische correlaties bij de IgA-nefropathie.

67 renal biopsies of children with IgA nephropathy, collected from 1970 to 1983 were analyzed semiquantitatively. Glomerular, tubular, vascular and interstitial lesions were scored and compared with clinical data in 56 patients. The number of cases registered and the severity and type of the glomerulopathy varied widely between centres. Histological parameters influencing significantly the outcome of the disease could not be detected.