The N = 1 randomized trial: A useful tool for assessing therapeutic efficacy in clinical practice

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these were adolescent females of Mediterranean or Asian origin. Two adult males from the same regions have been identified with this lesion. We recently treated an 11-year-old Venezuelan boy who presented with an acute illness characterized by fever, right lower quadrant abdominal pain, and emesis. At exploration for presumed acute appendicitis, he was found to have a partial distal heal obstruction secondary to involvement of the terminal 18 inches of ileum by a “cocoon” of adhesions. The reminder of the small intestine was enveloped by a thin membrane which was in continuity with the distal ileal membrane. The adhesions were lysed and an appendectomy performed. The patient had an uneventful recovery and is asymptomatic 3 months after the procedure. This patient represents the first example of idiopathic SP described in the Western hemisphere. The history, operative findings, and pathology are typical for this entity in every respect except for the sex of the patient. Idiopathic SP should be included in the differential diagnosis whenever unusual adhesions, especially involving the terminal ileum, are encountered in adolescent patients. The N = 1 Randomized Trial: A Useful Tool for Assessing Therapeutic Efficacy in Clinical Practice Jacob C. Lunger, Andrea L. Winthrop, Robert M. Issenman, McMaster University, Hamilton, Ontario

Assessment of therapeutic efficacy in children is complicated by fluctuations in disease severity, difficulty in interpreting symptoms, and variable patient responses. An N = 1 trial is used in an individual patient to assess the efficacy of a specific therapeutic intervention. The treatment in question is alternated with placebo, in a randomized order, over a number of study periods. Specific outcomes are recorded blindly by the family or nurses, and compared at the end of the study using paired statistical analysis. We present two pediatric surgical patients in which the effect of cisapride on gastroesophageal reflux (GER) was tested using this technique. Case 1 was a child who had a diaphragmatic hernia repaired at birth, and at age 2 developed persistent vomiting and gagging associated with documented GER. In a 6-week N = 1 trial (3 study periods), cisapride was associated with no significant difference in vomiting (0.7 Y0.7 days/wk) or gagging (2.0 v 0.7), but did result in a significant increase in stool frequency (4.3 v 7.0, P < .05). Since the symptoms of concern were not affected, cisapride was not used. Case 2 was a child who underwent esophageal atresia repair and 2 subsequent fundoplications. and presented with vomiting, coughing, and wheezing associated with recurrent GER. A 6-week N = 1 trial revealed a significant effect of cisapride on the incidence of vomiting (0.3 v 2.7 daysiwk, P < .05) and wheezing (1.0 v 2.7, P < .05), but not on the incidence of coughing. Cisapride was continued, with good results. These examples illustrate the value of an N = 1 trial in assessing the efficacy of a specific treatment, for well-defined symptoms, in an individual patient. This technique: (1) is inexpensive and simple, (2) can be used by the pediatric surgeon in daily practice, and (3) permits the rational use of effective therapy, and the abandonment of ineffective measures. Surgical Implications of Chronic Granulomatous Disease Jordan W. Ecketi, Stuart Abramson, Donald Anderson, Jefiey Starke, Mary L. Brandt, Texas Children’s Hospital, Cora and Webb Mading Depafiment of Surgery, Department of Pediatrics, Baylor College of Medicine, Houston, TX

Chronic granulomatous disease (CGD) is a rare, recessive disorder of phagocytic oxidative metabolism which results in recurrent, pyogenic infections. Current recommended prophylaxis consists of

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subcutaneous y-interferon and prophylactic antibiotics, which appear to decrease the frequency of serious infections. The diagnosis is suggested by multiple infections, unusual organisms, or poor surgical wound healing. The neutrophil Nitroblue Tetrazolium Test (NBT) is used to assess the oxidative potential of the neutrophil and is diagnostic for CGD if NBT is not reduced. The course of ten children with NBT confirmed CGD was reviewed. 80% of the children were male. The average age at first presentation was 9 months (range, 2 days to 4 years). 70% of the patients were diagnosed before age 2. Each child developed an average number of 9.7 infections (0.77 infections/year). The infections were varied in location, severity and infecting organism(s). Pneumonia (15), lymphadenitis (13), superficial abscess (lo), otitis media (10) and perirectal abscess (8) were the most common infections. Organisms cultured included gram-negative bacteria (14), gram-positive bacteria (ll), Aspergillus (2) and Candida (1). All ten children required surgical procedures for diagnostic or therapeutic complications of their CGD. The average number of procedures per child was 2.9 (range, 2 to 6). The most frequent procedures performed were: I&D soft tissue abscess (7), I&D perirectal abscess (3), thoracentesis (3), bronchoscopy (3) drainage of psoas abscess (I), diagnostic laparotomy for diffuse granulomas (1) drainage of lung abscess (1) right middle lobectomy (1) cystoscopy with bladder biopsy (1). One child underwent radiologic aspiration of a retrocardiac abscess and one child had endoscopic biopsy of duodenal granulomas causing gastric outlet obstruction. Three children had poor wound healing following their procedure and, in one case, the diagnosis of CGD was made by the surgical service because of the wound problem. Children with CGD invariably develop infections which require surgical intervention. Familiarity with CGD and it’s many presentations may lead to earlier diagnosis, appropriate prophylaxis, and a decrease in morbidity and mortality for these patients.

What Is the Benefit From Mass Screening for Neuroblastoma S. Suita, Y. Zaizen, H. Yano, H. Akiyama, Y Sera, K. Ueda, H. Tasaki, S. Miyazaki, K. Kawakami, Department of Pediatric Surgery, Kyushu University, Fukuoka, Japan

Since 1985, a nationwide program of mass screening for neuroblastoma has been underway for 6-month-old infants throughout Japan. By the end of 1989, the Committee of the Japan Neuroblastoma Mass Screening Study had surveyed 337 cases of the 383 cases that had been detected by this mass screening. Among them 330 (97.7%) were alive, only 3 (1%) were dead of the disease, and 4 (1.3%) died of other causes, indicating an improved prognosis for neuroblastoma found by screening. In order to evaluate population-based mortality statistics, and to compare neuroblastoma outcome in screened versus unscreened populations, we studied 200 patients with neuroblastoma registered in our region (population 15 million) from 198.5to 1990. The following results were obtained. (1) The total number of patients with neuroblastoma increased, compared to the previous S-year period (200 cases v 84 cases from 1980 to 1984). However. no significant difference was noted in the incidence of advanced stage (stage III and 1V) of neuroblastoma. (2) In the advanced stage group, overall survival rate in the screened group was lOO%, whereas in the unscreened group it was only 27.4%. (3) In the less than 12 months old group, 83 of 114 cases were found by mass screening. In the favorable group (stage I, II, and IVs), all patients, both screened and unscreened, are surviving except one who had high N-myc amplification (22 copies). In the advanced stage group, all patients in the screened group are surviving: whereas in the unscreened group only 6 of 12 cases are surviving; 5 died of tumor and one died from other causes. (4) Fourteen infants detected by