[Pediatric Crohn's disease in Tunisia]. / La maladie de Crohn de l'enfant en Tunisie.

UNLABELLED: Crohn's disease occur mainly in adults. However, pediatric onset forms are not rare and have many characteristics. AIM: to study clinical, diagnostic, therapeutic and evolutive characteristics of crohn's disease in tunisian children. METHODS: Retrospective multicenter study conducted in 10 pediatric departments on a period of 10 years (2000-2008) RESULTS : 43 children were included. The sex-ratio was 1.68. The mean age at the onset of the symptoms was 11+/-2.3 years (5-16 years). The age of onset was inferior to 10 years in 25 % of the children. The delay before management was superior to 1 year in 25% of cases. The initial symptoms were dominated by diarrhea (95%). Perineal manifestations were present at diagnosis in 30% of children and extra-digestive manifestations in 53%. Ileocolonic localization was the most frequent (46%). The initial disease flare was moderate in 83% of cases. The treatment was medical in 77 % of cases, nutritional and medical in 18.5%. Maintenance therapy was instituted in 86% of cases and consisted essentially in azathioprin (62%). The mean follow-up was 3 years and 4 months. 60% of the children had at least one acute flare. During evolution, 7% of children had anoperineal surgery and 11% an intestinal resection. CONCLUSION: Crohn's disease seems rare in Tunisia. The time of diagnosis is often delayed. The management is based on immunosuppressive therapy and nutritional support.

[Biochemical and molecular diagnosis of primary hyperoxaluria type 1: Tunisian study about 15 cases]. / Diagnostic biochimique et moléculaire de l'hyperoxalurie primaire de type 1: étude tunisienne à propos de 15 cas.

BACKGROUND: The primary type 1 hyperoxaluria (HP1) is the most frequent and severe form of the primary hyperoxaluriae. It is related to an enzymatic deficit in alanine glyoxylate aminotransferase (AGT). It is a recessive autosomic disease. Rare in Europe, it is responsible for 13% of the end stage renal failure in the Tunisian child. AIM: The aim of this work is to evaluate the biological and molecular examinations contributing with the early diagnosis and the follow-up of the HP1 patients and to test their response to pyridoxin. PATIENTS AND METHODS: A prospective study of 15 children who have oxaluria lower than 500 µmol/l and normal renal function is carried out. The cristalluria study, oxaluria and the glycolate-glycerate urinary ratio were carried out on all the patients. The so-called mutation maghrebean T853 (Ile244 Thr) was detected by direct sequencing of the exon 7 gene AGXT. The response to pyridoxin was tested among 13 patients. RESULTS: The oxaluria concentration was greater or equal to 1000 µmol/l in nine cases (60%) and ranging between 600 and 1000 µmol/l in the remaining cases. The oxaluria flow was significantly high depending on the age. The glycolaturia was high among eight patients (57%). In 61,5% of the cases, the most frequent crystalline species was whewellite (C1). The "maghrebin" mutation was identified in nine patients at the heterozygous state, showing 25% allelic frequency. The response to pyridoxin was observed in the 13 tested cases. CONCLUSION: The HP1 is frequent in our country from where the need for an early diagnosis. The use of simple biochemical tools such as the study of the cristalluria, the morphological analysis of stones and the oxaluria allow to direct the diagnosis towards a HP1, confirmed by the glycolaturia determination. The molecular biology is required in the atypical forms.

[Urinary stones in Tunisian children, based on series of 187 cases]. / La lithiase urinaire chez l'enfant tunisien. Etude à propos de 187 cas.

OBJECTIVE: The aim of this study is to define epidemiologic and structural particularities of urinary stones in Tunisian children. PATIENT AND METHODS: Between 1995 to 2007, 187 stones of Tunisian children were studied. Structural analysis was performed by infrared spectrophotometry. RESULTS: We analyzed 187 stones from 122 boys and 65 girls. Their age ranged from two months to 18 years. Our study shows a male predominance with a sex ratio of 1,88. Stones were renal in 64.8%, ureteral in 20.6% and 14.6% were vesical. Whewellite was the main component (49,2% of stones) with a female predominance. Among phosphatic stones, carbapatite was in the lead (10.7%) followed by struvite (7%), which predominate in male. CONCLUSION: The epidemiological profile of urinary stones in children in Tunisia is situated between that observed in developed countries and that observed in developing countries.

Urolithiasis in Tunisian children: a study of 120 cases based on stone composition.

The composition of urinary stones in children depends on socioeconomic conditions and hygiene, geographical area, and dietary habits. We analyzed urinary stones from 120 consecutive Tunisian children (81 males, 39 females) aged 5 months to 15 years. The stone was located in the upper urinary tract in 91 cases (76%). Stone analysis included both a morphological examination and an infrared analysis of the nucleus and the inner and peripheral layers. The main components of bladder calculi were whewellite (69%) and struvite (22%), whereas the main component of upper urinary tract calculi was whewellite (67%). The nucleus of bladder stones was composed of ammonium urate (45%), struvite (28%), cystine (10%), and carbapatite (7%). The nucleus of kidney and ureteral calculi was mainly composed of ammonium urate (38%), whewellite (24%), carbapatite (13%), or struvite (11%). Based on stone composition, urinary tract infection was involved in the nucleation or growth of a third of calculi. Endemic urolithiasis involving simultaneous nutritional, metabolic, and infectious factors, and defined by its nucleus composed of ammonium urate without struvite, represented 40% of cases. Exclusive metabolic factors - including genetic diseases such as primary hyperoxaluria, cystinuria, and hypercalciuria - were responsible for less than 25% of cases.

[Urinary calculi in children: contribution of anamnesis, biological exploration and physical analysis of calculi to the etiological diagnosis]. / La lithiase urinaire de l'enfant: contributions de l'anamnèse, de l'exploration biologique et de l'analyse physique des calculs au diagnostic étiologique.

BACKGROUND: It is always of importance to define the cause of urinary calculi disease in children to prevent recurrence and possible impairing of renal function. Nevertheless, etiology is not always easy to prove and must be deduced from both clinical and biological arguments. PATIENTS AND METHODS: The aim of this prospective study including 39 Tunisian children with urinary stones was to identify etiology and stone risk factors and detail the part of clinical and biological data and results of physical analysis of stones in determining the cause of the stone. RESULTS: In 31 cases among 39, clinical and biological data were not sufficient to identify clearly the stone etiology. When considering the structure and stone composition, the cause of the stone could be determined in 97.4% of the cases. An inherited disease was found responsible for the stone in 11 children, urinary tract infection in 13 cases, idiopathic hypercalciuria in nine cases and a nutritional deficiency disease in seven cases. In one case, polycystic kidney disease with metabolic risk factors could explain the stone process. No precise etiology was found in one case. Among infection stones, struvite stones could be related to urea-splitting bacteria while other calculi, containing whitlockite and protein matrix could be related to other micro-organisms. Earlier severe chronic diarrhoea episodes were noted in six among seven children presenting stones with a nucleus mainly composed of ammonium urate. CONCLUSION: Clinical data, biological data from both urine and blood of the patients and also the structure and composition of the stones are needed to identify the cause of urinary calculi. Such a procedure could provide the stone etiology in most cases.

[Primary hyperoxaluria: Tunisian experience apropos of 24 pediatric cases]. / Hyperoxalurie primitive: l'expérience tunisienne à propos de 24 cas pédiatriques.

We report on 24 children (10 girls) presenting with primary hyperoxaluria. The mean age at diagnosis was 6.3 years (range: 3 months-14.8 years). The mean interval between initial symptom and diagnosis was 1.3 year. The average follow-up period was 22 months (range: 1-60 months). At the time of diagnosis the renal function was normal in 6 children, moderately altered in 1 and severely in 17. During the follow-up the renal function remained stable in 6 patients, improved in 2, deteriorated in 4. The 12 patients with end-stage renal disease at diagnosis remained unchanged. Urolithiasis were present in all patients older than 2 years, and in 1 among the 5 infants. Medullary nephrocalcinosis was observed in 3 patients in whom the renal function was preserved. Diffuse nephrocalcinosis was present in all patients with end-stage renal failure. Improvement of renal function was secondary to stone removal in 2 patients. Extracorporeal shock wave lithotripsy performed in 7 patients was efficient only in 3. In 10 patients oxalate bone disease was correlated with both renal function and dialysis duration, whereas retinal involvement noted in 6 patients was not.

[Ocular signs of primary hyperoxaluria type I]. / Signes oculaires de l'hyperoxalurie primitive de type I.

PURPOSE: To report the results of ophthalmological examination of 14 patients with primary oxalosis of type I, and to appreciate the diagnostic value of these signs. MATERIAL AND METHODS: Fourteen patients, 7 girls and 7 boys with an average age of 8-35 years (3 months - 15 years). Ten patients had renal failure, 2 died without dialysis and eight were treated with dialysis; 5 out of 8 had hemodialysis and the duration of this treatment varied between 3 months and 3.5 years, 3 out of 8 had peritoneal dialysis. RESULTS: Visual acuity was 10/10 in 11 cases and we noted a vision of 5/10 in one eye in one case. Ocular fundus examination was normal in 7 cases. In 5 cases, it showed numerous minute white round flecks at the posterior pole and near the retinal vessels which probably correspond to deposition of calcium oxalate crystals. In one case we found a diffuse retinal pigment atrophy and in another case a sectorial papillar atrophy without loss of vision. CONCLUSION: This flecked retinopathy can occur before hemodialysis or after a few months or years of hemodialysis. There is no correlation between duration of dialysis and ocular lesions.

[Infantile forms of primary hyperoxaluria type I: apropos of 4 cases]. / Les formes infantiles de l'hyperoxalurie primaire de type I: à propos de quatre cas.

BACKGROUND: Approximately 10% of the cases with primary hyperoxaluria type I present before age 1 and are usually classified as neonatal primary oxaluria. CASE REPORTS: Four unrelated infants, aged 3 to 9 months, were admitted for severe renal failure due to primary hyperoxaluria type I. Other affected members were known in two of these four families but the disease was not present at the same age in each family. Echogenicity of kidneys was increased in all the patients and calcium oxalate crystals were seen in the collecting system and within the renal parenchyma. Urolithiasis was not present. Treatment of renal failure, ie, peritoneal dialysis, was uneffective in one patient and was interrupted in two others because organ transplantation was impossible. CONCLUSIONS: The infantile forms of primary hyperoxaluria type I may be rapidly complicated by severe renal failure in the absence of urolithiasis.

End-stage renal disease of the Tunisian child: epidemiology, etiologies, and outcome.

From December 1989 to December 1993, 90 children under 15 years were admitted to our department for end-stage renal disease; 9 children were less than 5 years and 28 were aged between 5 and 10 years. The sex ratio (M/F) of the children was 2.1. The estimated incidence of pediatric end-stage renal disease in Tunisia is 7 new cases per year and per million child population under 15 years. The chief etiologies of end-stage renal disease are glomerulonephritis (19%), hereditary nephropathies (29%), and malformative uropathies (13%); 26% of the end-stage renal diseases are of unknown etiologies. Our findings, compared with the European data, show a particularly high frequency of primary hyperoxaluria (13.5%) and an unusual proportion of male subjects.

[Etiologic factors of urinary lithiasis in Tunisian children]. / Facteurs étiologiques de la lithiase urinaire de l'enfant en Tunisie.

Fifty-five Tunisian children with urinary stones, between the ages of 8 months and 15 years, underwent morphological and infrared spectrophotometric analysis of their stones. This study provides an approach to the aetiological profile of urinary stones in Tunisian children. The nucleus of the stones was composed of acidic ammonium urate in 48% of cases with a morphology suggestive of phosphorus deficiency associated with a history of diarrhoea. In 24% of cases, the nucleus contained struvite indicating the presence of urinary tract infection by urease-positive bacteria. The main growth factors of urinary stones were hyperoxaluria and urinary tract infection. In 5 cases, the stones were due to a hereditary lithogenic metabolic disease : cystinuria in 1 case and primary hyperoxaluria in 4 cases.

[Value of extracorporeal shockwave lithotripsy in primary hyperoxaluria type I]. / Intérêt de la lithotritie extracorporelle dans l'hyperoxalurie primaire de type I.

BACKGROUND: Application of extracoporal shock wave lithotripsy (ESWL) has revolutionized the management of many types of urolithiasis, including that observed in primary hyperoxaluria where surgical attempts to remove calculi sometimes result in worsening of renal function. CASE REPORTS: Three unrelated patients aged 8, 10 and 11 years, respectively, with type I primary hyperoxaluria, suffered from recurrent bouts of abdominal pain (two patients) or anemia (one patient). Two patients had chronic renal failure. Plain abdominal films and ultrasonography showed several large bilateral stones. ESWL was applied to the three patients permitting complete removal of stones following three sessions in one patient and partial removal following four sessions in the second patient who developed infection after the first session with transitory increase in creatinemia. Several sessions of ESWL failed to fragment stones in the third patient. CONCLUSION: ESWL may represent a safe procedure for attempting stone removal in patients with primary hyperoxaluria.

[Radiological signs of type I primary hyperoxaluria]. / Les signes radiologiques de l'hyperoxalurie primaire de type I.

The authors report the radiological signs observed in 14 patients between the ages of 3 months and 16 years, suffering from type I primary hyperoxaluria. Four of these patients were being treated conservatively for renal failure and ten had reached end-stage renal failure. Stones were demonstrated in 9 patients. Nephrocalcinosis was present on the plain abdominal x-ray in 6 patients before dialysis, and in all patients dialysed for more than 3 months. Bone signs characteristic of type I primary hyperoxaluria were only observed in children with end-stage renal failure. Metaphyseal dense bands were revealed in 5 patients. Metaphyseal clear bands, observed in 4 patients, occurred later and appeared to replace dense bands which moved towards the diaphysis. The other signs detected were osteosclerosis of the vertebrae and ilium (4 patients) and epiphyseal subchondral clear bands (one patient).

A unique mutation underlying carbonic anhydrase II deficiency syndrome in patients of Arab descent.

We have investigated, in the genomic DNA of ten Tunisian patients, the presence of a splice junction mutation at the 5' end of intron 2 in the carbonic anhydrase II gene (CAII) previously described in six CAII-deficient patients presumed to be of Arab origin. All our patients were homozygous for this mutation and were mentally retarded, a characteristic feature of the phenotype of patients with an Arabic background. This mutation is found exclusively in patients with an Arabic background and thus may be confined to this ethnic group.