Detection of Cryptosporidium parvum in raw milk by PCR and oligonucleotide probe hybridization.

Cryptosporidium spp. are potential contaminants of food. Suspected cases of food-borne cryptosporidiosis are rarely confirmed because of the limited numbers of oocysts in the samples and the lack of sensitive detection methods adaptable to food. PCR was investigated as a means of overcoming this problem. A PCR assay was designed for the specific amplification of a previously sequenced portion of an oocyst protein gene fragment of Cryptosporidium parvum (N. C. Lally, G. D. Baird, S. J. McQuay, F. Wright, and J. J. Oliver, Mol. Biochem. Parasitol. 56:69-78, 1992) and compared with the primer set of Laxer et al. (M. A. Laxer, B. K. Timblin, and R. J. Patel, Am. J. Trop. Med. Hyg. 45:688-694, 1991). The PCR products were hybridized with digoxigenin-labeled internal probes and detected by chemiluminescence to enhance sensitivity. The two sets of primers were compared with regard to their sensitivity and specificity by using a variety of human and animal isolates of C. parvum and related parasites. Both assays enabled the detection of 1 to 10 oocysts in 20 ml of artificially contaminated raw milk. The assay based on the PCR set and probe of Laxer et al. detected DNAs from Eimeria acervulina and Giardia intestinalis. The new assay has good specificity for C. parvum bovine isolates and hence has a better potential for monitoring the prevalence of C. parvum in raw milk and other environmental samples.

Prevalence, detection and control of Cryptosporidium parvum in food.

The role of Cryptosporidium parvum as a foodborne pathogen has not been well documented. Epidemiological features of this parasitic protozoon lead to the assumption that the incidence of cryptosporidiosis due to contaminated food is under-estimated. The high prevalence of C. parvum among dairy herds has increased the spread of oocysts in the farm environment, and their potential presence in raw milk and other raw foods. In October 1993, the first well-documented foodborne outbreak was reported in Maine, USA, and was caused by contaminated hand-pressed apple cider. Although various cases of cryptosporidiosis among humans have pointed to raw milk and other raw foods as possible sources of infection, a conclusive demonstration of foodborne cryptosporidiosis has rarely been established. The limited numbers of oocysts in the suspected samples and the lack of sensitive detection methods adapted for oocyst detection in food contribute to this under-reporting. This review paper discusses various aspects of Cryptosporidium spp. and cryptosporidiosis, including the routes of transmission, the control of oocysts in food, and the available detection methods. The polymerase chain reaction (PCR) combined with DNA probe hybridization is a promising detection method. Recent knowledge on the molecular biology of the parasite for the development of new PCR assays and their potential use in the detection of C. parvum in food are described.

[Endoscopic treatment of vesico-ureteral reflux using teflon injections]. / Traitement endoscopique du reflux vésico-urétéral par injections de téflon.

We have reviewed 124 patients with vesicoureteral reflux who were treated by endoscopic injection of polytetrafluoroethylene (Teflon) in four institutions. Of these patients 71 had bilateral reflux and 53 had unilateral reflux. In all, 195 ureters were treated. Reflux was primary in 94 cases (143 ureters) and secondary in 30 cases (52 ureters). Only 118 ureters (60.5%) showed no more reflux after a single injection. Seventy-seven ureters needed a second or third Teflon injection to control their reflux. In this group, reflux was cured in 46 ureters (23.6%) for a total cure rate by Teflon injection of 84.1%. Thirty-one ureters (15.9%) needed reimplantation (follow-up ranged from 1-4 years). In this study we assessed results in relation to the grade and type of reflux, the injected dose of Teflon and the technique used. The possible causes of failure and the reported complications are discussed.

Maturation of the external urinary sphincter: a comparative histotopographic study in humans.

The developmental anatomy of the striated urinary sphincter remains controversial and is scantly documented in children. We compared its structure and configuration in the fetus, infant and adult to determine anatomical differences among these groups. We removed 25 postmortem specimens from fetuses, infants and children, which were fixed and stained for histological study. Ages ranged from 14 weeks of gestation to 12 years postpartum. Transverse and mid sagittal sections were obtained from the bladder neck to the membranous urethra in male and the whole urethra in female subjects. At the level of the membranous urethra in male and mid urethra in female subjects the striated muscle fibers completely encircle the urethra and join behind it to form a tail-like structure that runs posteriorly towards the perineal body. This structure is mid sagittal in male and mediolateral in female subjects. At 3 to 4 months of life, at the level of the bulbourethral glands the tail disappears; the striated sphincter becomes horseshoe-shaped and its 2 branches bifurcate posteriorly to envelop these glands. The urethral striated sphincter consists of scantly dispersed muscle fibers in the fetus. In young infants it becomes well defined in both sexes with the presence of a tail-like structure that characterizes this age group. In older subjects this tail disappears and the sphincter assumes a horseshoe or omega-shaped configuration as splitting of the sphincter progresses caudo-cranially with development. We attempt to determine whether the ring configuration of the voluntary sphincter contributes to high voiding pressures that are reported to occur in some newborns and infants.

Transitional hydronephrosis of the newborn and infant.

Between 1986 and 1988, 187 hydronephrotic renal units were discovered antenatally in 134 subjects and confirmed in the neonatal period. Of these cases 119 (64%) were due to anomalies of the ureteropelvic junction. The remainder (36%) were due to various congenital uropathic conditions. Investigation consisted of renal ultrasonography, voiding cystourethrography and diuretic renography with 99mtechnetium-diethylenetriaminepentaacetic acid augmented with furosemide. Of the 119 renal units 36 (30%) underwent pyeloplasty, while 42 (35.7%) were considered normal without obstruction or dilatation. In 41 units (34.3%) diuretic renography showed partial obstruction or dilatation without obstruction that washed out readily with furosemide. Serial renal ultrasonography and renography were performed in these patients. A 12-month followup showed improvement or stabilization in 80% of the renal units and deterioration to significant obstruction in 20%. In attempting to identify the renal units that were most at risk for deterioration, it was realized that the initial ultrasound had a predictive role. None of the mildly hydronephrotic units deteriorated, whereas 14% of the moderately hydronephrotic and 32% of the markedly hydronephrotic units showed further deterioration. However, whether diuretic renography initially demonstrated partial obstruction or dilatation without obstruction, the ultimate outcome could not be predicted. Based on this experience an algorithm is proposed for the evaluation and management of antenatally detected hydronephrosis with currently available imaging techniques.

[The role of therapeutic laparoscopy in the surgical treatment of intra-abdominal testes in children]. / La place de la laparoscopie thérapeutique dans le traitement chirurgical des testicules intra-abdominaux chez l'enfant.

Over a period of four years (September 1986 to September 1990), 32 impalpable testes were found in 24 cryptorchid boys at Sainte-Justine Hospital, Montreal. 11 (34%) of the impalpable testes were intra-abdominal. Of these, 5 testes were hypoplastic and were removed, 3 by a traditional inguinal transperitoneal orchiectomy and 2 by laparoscopy; 2 testicles were brought down by classic orchiopexy whereas two others underwent a Fowler-Stephens procedure. One of these underwent preliminary laparoscopic clipping of the spermatic vessels followed six months later by open surgery to bring the testis down on the vas and deferential artery and its well-developed collateral circulation. One patient underwent a two-stage open orchiopexy and another had unilateral testicular autotransplantation. The literature is reviewed and surgical indications for therapeutic laparoscopy are discussed.

Intramural Teflon injection of the ureter for treatment of vesicoureteral reflux: sonographic appearance.

Endoscopic injection of Teflon paste under the submucosal portion of the ureter in the bladder is a new treatment for vesicoureteral reflux. Twenty-one children at The Montreal Children's Hospital and at St. Justine Hospital were treated with this technique over a 2-year period. In 15 children, abdominal sonography was performed 1-5 days after Teflon paste injections. Follow-up sonograms performed 5 weeks to 1 year after the procedure are available in nine children. Sonographically, the Teflon paste at the injection site appears as a hyperechoic focus within the bladder wall with distal shadowing seen postoperatively and on follow-up examinations. This finding occurred in 22 (88%) of 25 treated ureters. The location of Teflon paste after injection as viewed via cystoscopy is correlated with the sonographic appearance. This preliminary report suggests that sonography is useful in determining the location and size of the Teflon mass, in evaluating surrounding soft tissues at various time intervals after injection, and in assessing possible complications such as obstruction.

Perforated appendicitis presenting as torsion of spermatic cord.

A case of perforated appendicitis presenting as acute scrotal swelling and erythema is reported. A hydrocele containing cloudy fluid was encountered on surgical exploration suggesting the intra-abdominal pathology.

Orthoplasty in epispadias.

Orthoplasty (a term used in Europe to refer to chordee excision and penile straightening) in patients with epispadias has provided less than ideal results in the past. We propose a sequential stepwise approach for the assessment and correction of the corporeal deformity, incorporating dermal grafts on the dorsal aspect of the corpora cavernosa when necessary to achieve functional penile lengthening and straightening. Success, defined as significant improvement in functional penile length, a penis that dangles at 45 degrees below the horizontal and over-all improvement in cosmetic result, was achieved in 7 of 8 patients.

Effects of oxybutynin on vesicoureteral reflux in children.

We reviewed retrospectively 40 children seen from 1980 to 1984 with vesicoureteral reflux in 53 ureters. All patients had a hyperreflexic bladder on urodynamic evaluation with or without vesicoperineal dyssynergia but they were otherwise neurologically normal. All except 1 child received prophylactic antibiotics. Of the children 37 received oxybutynin therapy for bladder hyperreflexia for 3 to 18 months. Reflux disappeared or became grade I in 62.3 per cent of the ureters. Of the children manifesting urinary incontinence at the time of urodynamic study reflux disappeared or became grade I in 78.6 per cent. Reflux resolved or became grade I in 20 per cent of the children with no urinary incontinence. Of those patients with recurrent reflux at the onset of urinary incontinence and bladder instability reflux resolved or became grade I in 80 per cent. Oxybutynin therapy for hyperreflexic bladder resulted in an average increase in bladder capacity of 97 cc (54.2 per cent), which was maintained after cessation of treatment. These data suggest that bladder instability can be an important factor in causing and perpetuating reflux. Therapy aimed at decreasing intravesical pressure will enhance resolution or downgrading of reflux.

Urolithiasis in pregnancy.

A retrospective analysis of pregnancies complicated by urolithiasis in a major referral center for high-risk pregnancies indicated an incidence of 1:2,534. In contrast to previous series, the majority of patients were primiparas. The judicious use of hydration, analgesics and antibiotic therapy resulted in a high rate of spontaneous passage of stones initially localized below the renal pelvis and a favorable outcome for all pregnancies.

[Role of urinary diversion in pyeloplasty (author's transl)]. / Le rôle de la dérivation urinaire dans la pyéloplastie.

A retrospective study was made of 105 pyeloplasties in 103 patients over a period of 18 years with the aim of precisely determining the role of urinary diversion in the post-operative period by nephrostomy tube and/or ureteral splint. A group of patients undergoing the same type of procedure, but without diversion, served as controls. Short-term results are evaluated clinically and radiologically and long-term results are evaluated by review of X-ray charts. These results were submitted to statistical analysis that have helped to demystify the role played aby diversion in pyeloplasties.

Pyeloplasty: to divert or not to divert?

The use of diversion in conjunction with pyeloplasty has been a matter of continuous debate for a number of years. In consequence the matter has been left to the urologist's individual preferences with no objective data to support these preferences. Herein the authors present an analysis of 105 pyeloplasties performed by four surgeons over a period of eighteen years with a view to determine the place and type of diversion in relation to the surgical technique used and the long-term effects of such diversion or abstinence thereof.

[Renal and perinephritic abscesses in children]. / Abcès rénal et périrénal chez l'enfant.

One child with a pure perinephric abscess and three with renal abscesses, one of which had perinephric extension, are described. All presented with a long course of subacute infection leading to localizing symptoms or signs in the flank. The diagnosis was confirmed by radiologic examination. All the abscesses were surgically drained at various intervals after diagnosis, while the patients were receiving antibiotic therapy. Salvage of renal function was possible in all cases. A rational approach to the diagnosis and management of such abscesses is emphasized.

Avulsion of ureter by blunt trauma.

Six cases of avulsion of the upper ureter by blunt trauma are presented: 5 in children and one in an adult. One of these also involved the entire renal pedicle. A review of the literature shows that this type of trauma is rare, about 30 cases having been reported. They are seen mostly in children, and the right kidney is more prone to injury. Often, there is absence of hematuria which leads to considerable delay in diagnosis and surgical repair. On account of this delay, hydronephrosis, infection, and sometimes pseudocyst formation can complicate the initial pathologic condition. Despite these delays, successful repair can be accomplished and the kidney salvaged. In some instances, as we found out in our cases, a retrograde pyelogram was helpful in establishing the diagnosis and localizing the site of the lesion preoperatively.

Cutaneous transureterostomy in children.

Cutaneous transureterostomy was done on 18 patients with chronically dilated upper tracts. The operation is simple with minimal immediate complications. Long-term results are good despite the frequent persistence of chronic urinary infection and dilatation of the ureters, which are attributable to their persistent damage. We believe that cutaneous transureterostomy represents a good type of urinary diversion for these children.