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S M Borowitz

Publications and source records attributed to S M Borowitz.

At least 19 recordsLinked to original sources

Manifestations and linkage analysis in X-linked autoimmunity-immunodeficiency syndrome.

The clinical findings of a kindred with an X-linked disorder are characterized by autoimmune polyendocrinopathy, enteropathy with villous atrophy, chronic dermatitis, and variable immunodeficiency. Linkage analysis was performed on 20 members of the affected kindred to determine the location of the responsible locus. Informative recombinations limited the region to an approximate 20 cM interval bordered by DXS1055 and DXS1196/DXS1050. Multipoint analysis generated a lod score >3 for the region contained between DXS8024 and DXS8031. The candidate region includes the Wiskott-Aldrich syndrome (WAS) locus. Evaluation of the Wiskott-Aldrich syndrome protein gene by single strand conformational analysis, heteroduplex analysis, and direct sequencing of the 12 exons in an affected male and two carrier females revealed no abnormalities. We conclude that this kindred has an X-linked disorder, distinct from WAS, that results in autoimmunity and variable immunodeficiency. The responsible locus maps to the pericentromeric region Xp11.23 to Xq21.1.

Autoimmunity↗

Information collected during the residency match process does not predict clinical performance.

OBJECTIVE: To determine whether information collected during the National Resident Matching Program (NRMP) predicts clinical performance during residency. METHODS: Ten faculty members rated the overall quality of 69 pediatric house officers as clinicians. After rating by the faculty, folders were reviewed for absolute rank on the NRMP match list; relative ranking (where they ranked in their postgraduate year 1 [PGY-1] group); scores on part I of the National Board of Medical Examiners (NBME) examination; grades during medical school pediatrics and internal medicine rotations; membership in the Alpha Omega Alpha Medical Honor Society; scores of faculty interviews during intern application; scores on the pediatric in-service examination during PGY-1; and scores on the American Board of Pediatrics certification examination. RESULTS: There was substantial agreement among faculty raters as to the overall quality of the residents (agreement rate, 0.60; kappa = 0.50; P = .001). There was little correlation between faculty ratings and absolute (r = 0.19; P = .11) or relative (r = 0.20; P = .09) ranking on the NRMP match list. Individuals ranked in the top 10 of the match list had higher faculty ratings than did their peers (mean +/- SD, 3.66+/-1.22 vs. 3.0+/-1.27; P = .03), as did individuals ranked highest in their PGY-1 group (mean +/- SD, 3.88+/-1.45 vs. 3.04+/-1.24; P = .03). There was no correlation between faculty ratings and scores on part I of the NBME examination (r = 0.10; P = .49) or scores on the American Board of Pediatrics certification examination (r = 0.22; P = . 11). There were weak correlations between faculty ratings and scores of faculty interviews during the intern application process (r = 0.27; P = .02) and scores on the pediatric in-service examination during PGY-1 (r = 0.28; P = .02). There was no difference in faculty ratings of residents who were elected to Alpha Omega Alpha during medical school (mean +/- SD, 3.32+/-1.21) as compared with those who were not (mean +/- SD, 3.08+/-1.34) (P = .25). CONCLUSIONS: There is significant agreement among faculty raters about the clinical competence of pediatric residents. Medical school grades, performance on standardized examinations, interviews during the intern application process, and match-list ranking are not predictors of clinical performance during residency.

Adult↗

Differences in toileting habits between children with chronic encopresis, asymptomatic siblings, and asymptomatic nonsiblings.

No studies have compared toileting-specific behaviors of encopretic children with those of asymptomatic children and have controlled for environmental factors such as parental attitudes, parenting styles, and bathroom facilities. This study prospectively examined the toileting habits of 86 chronically encopretic children compared with those of 27 asymptomatic siblings and 35 asymptomatic nonsiblings. Although encopretic children experienced significantly more soiling than did controls, the total number of daily bowel movements passed in the toilet (+/-SD) was comparable in the three groups (.92 +/- .76 in encopretic children compared with 1.14 +/- .43 and 1.08 +/- .47 in siblings and nonsiblings, respectively). Encopretic children experienced pain with defecation more often than did controls. During the 14-day study period, encopretic children complained of pain on 2.75 +/- 4.03 days compared with .58 +/- 1.84 days among sibling controls and 2.31 +/- 3.21 days among nonsibling controls. The mean pain score in encopretic children was .76 +/- 1.00 compared with .05 +/- .15 and .26 +/- .38 among siblings and nonsiblings, respectively. All three groups of children sat on the toilet without parental prompting the same number of times each day. In summary, children with chronic encopresis do not seem to avoid toileting, and they exhibit toileting behaviors that are very similar to those of asymptomatic siblings as well as to those of nonsibling controls.

Animals↗

The origin, content, and workload of e-mail consultations.

CONTEXT: Despite the common use of e-mail, little beyond anecdote or impressions has been published on patient-clinician e-mail consultation. OBJECTIVE: To report our experiences with free-of-charge e-mail consultations. DESIGN: Retrospective review of all e-mail consultation requests received between November 1, 1995, and June 31, 1998. SETTING AND PARTICIPANTS: Consecutive e-mail consultation requests sent to the Division of Pediatric Gastroenterology at the Children's Medical Center of the University of Virginia in Charlottesville. MAIN OUTCOME MEASURES: Number of consultation requests per month, time required to respond, who initiated the request and their geographic origin, and the kind of information requested in the consultation. RESULTS: During the 33-month period studied, we received 1239 requests, an average (SD) of 37.6 (15.9) each month. A total of 1001 consultation requests (81%) were initiated by parents, relatives, or guardians, 126 (10%) by physicians, and 112 (9%) by other health care professionals. Consultation requests were received from 39 states and 37 other countries. In 855 requests (69%), there was a specific question about the cause of a particular child's symptoms, diagnostic tests, and/or therapeutic interventions. In 112 (9%), the requester sought a second opinion about diagnosis or treatment for a particular child, and 272 consultations (22%) requested general information concerning a disorder, treatment, or medication without reference to a particular child. A total of 1078 requests (87%) were answered within 48 hours of the initial request. On average, reading and responding to each e-mail took slightly less than 4 minutes. CONCLUSION: E-mail provides a means for parents, guardians, and health care professionals to obtain patient and disease-specific information from selected medical consultants in a timely manner.

Communication↗

Percutaneous endoscopic gastrostomy without an antireflux procedure in neurologically disabled children.

In children with major neurologic impairment, gastrostomies are often used to alleviate malnutrition and feeding difficulties. There has been a trend toward performing "protective" antireflux surgery in these children. Nineteen children with major neurologic impairment and feeding failure were prospectively evaluated and followed up after placement of a percutaneous endoscopic gastrostomy (PEG) without any antireflux procedure. Mean age at PEG placement was 34 months with mean follow-up of 20.7 months. All parents would recommend PEG to families with disabled children, and if given the chance, 95% would elect PEG again for their child. No child developed choking, gagging, or retching postoperatively. At the time of follow-up, postoperative gastroesophageal reflux did not appear to be a major clinical problem.

Adolescent↗

Lack of correlation of anorectal manometry with symptoms of chronic childhood constipation and encopresis.

UNLABELLED: Chronic constipation is an extremely common problem in children. Many authors have advocated using anorectal manometric examination during evaluation of chronic childhood constipation and encopresis as a means of developing individualized modes of treatment. PURPOSE: This study was designed to prospectively examine frequency and severity of symptoms of childhood constipation and encopresis and associate these symptoms with anorectal manometric findings. METHODS: Forty-four children with chronic constipation participated in the study. Before performing anorectal manometry, bowel-related symptoms were collected for two consecutive weeks with a computerized voice mail system. Anorectal manometry was performed using a triple lumen catheter attached to a hydraulic manometry infusion system. RESULTS: Frequency of voluntary bowel movements did not correlate with any manometric parameters. Frequency of fecal soiling, age at onset of symptoms, and duration of symptoms were all highly correlated with degree of sphincter spasm during attempted defecation; however, none of these variables correlated with any other manometric parameter. Amount of pain associated with bowel movements correlated with frequency of soiling and was inversely correlated with maximum squeeze pressure but was not correlated with any other manometric parameter. CONCLUSIONS: In children with chronic constipation and encopresis, sphincter spasm demonstrated with anorectal manometry is highly correlated with frequency of fecal soiling, age at onset, and duration of symptoms; however, none of the other commonly measured manometric parameters appear to correlate with symptoms of chronic childhood constipation and encopresis.

Age of Onset↗

Impact of a computerized patient tracking system in a pediatric clinic.

A computerized patient tracking system with an intuitive graphical interface was deployed in a large multidisciplinary pediatric outpatient clinic and has been enthusiastically embraced by both physicians and non-physician staff. Usage of the computerized patient tracking system has been associated with a significant decrease in the total time patients spend in the clinic. The total duration of an average patient visit has declined from 99.25 +/- 57.44 minutes to 66.94 +/- 30.47 minutes (p = 0.03). Most of this decrease has been due to a decrease in total waiting time from 54.17 +/- 37.61 minutes to 27.29 +/- 14.05 minutes (p = 0.006). Usage of the patient tracking system has also been associated with a significant increase in examination room utilization during peak business hours from 58.47 +/- 21.18% to 64.49 +/- 13.38% (p = 0.0329).

Ambulatory Care Facilities↗

Long-term follow-up of medically treated childhood constipation.

We describe the long-term (mean 6.8 years) follow-up of 43 children treated medically for chronic constipation and encopresis. Overall outcome was quite good. Thirty children (70%) were entirely asymptomatic at follow-up. Intermittent mild constipation persisted in 13 patients; only two required persistent but infrequent laxative therapy. Encopresis persisted in three of 17 children who initially reported this symptom, and was associated with significant behavioral problems.

Adolescent↗

Crohn's disease complicating cystic fibrosis.

We report the 10th known case of Crohn's disease associated with cystic fibrosis. Because the symptoms of Crohn's disease may easily be confused with those of cystic fibrosis, this association probably exceeds that predicted by existing prevalence data.

Child, Preschool↗

Using a computerized patient record to reengineer an outpatient clinic.

By employing process flow analysis and work redesign techniques during the design and implementation of a computerized patient record in the pediatric outpatient clinics at the University of Virginia Health Sciences Center, we have developed a database of clinical observations while simultaneously shortening the time that patients spend waiting in the pediatric clinics and decreasing the number of support staff employed within the clinics.

Ambulatory Care Information Systems↗

Oral dysfunction following Nissen fundoplication.

In this case report we describe a child with mild neurologic impairment who developed debilitating gagging and retching, and severe oral-motor dysfunction following Nissen fundoplication and gastrostomy tube placement. All oral intake ceased after the operation. Evaluation for postoperative dumping syndrome was negative, and the child's symptoms failed to improve despite numerous medical and surgical measures. However, immediately following reversal of the Nissen fundoplication, the child's gagging and retching ceased, and his oral-motor function began to improve. This is a previously undescribed complication of Nissen fundoplication, a surgical procedure commonly employed in children with neurologic impairment.

Deglutition Disorders↗

Glucocorticoids inhibit intestinal phosphate absorption in developing rabbits.

Children are apt to develop osteoporosis during chronic glucocorticoid therapy, in part due to suppression of intestinal calcium absorption. Little is known about effects of glucocorticoids on phosphate absorption. To characterize effects of glucocorticoids on intestinal phosphate transport, 4-wk-old suckling rabbits were injected with methylprednisolone. Twenty-four hours following injection, phosphate transport was studied in brush border membrane vesicles. Vesicles from steroid-treated and control animals demonstrated sodium-phosphate cotransport. Uptake was significantly greater in controls than in methylprednisolone-treated animals. Controls demonstrated an "overshoot," in that peak phosphate uptake exceeded equilibrium by nearly 100%, whereas minimal overshoot was observed in methylprednisolone-treated animals. Vmax and Km for sodium-dependent phosphate transport were 556.6 +/- 13.2 pmol.mg protein-1.10 s-1 and 0.051 +/- 0.01 mmol/L, respectively, for controls and 285.4 +/- 3.5 pmol.mg protein-1.10 s-1 and 0.044 +/- 0.01 mmol/L for methylprednisolone-treated animals. Although phosphate uptake was greater in controls than in methylprednisolone-treated animals, maximal stimulation of phosphate uptake occurred between 75 and 100 mmol/L sodium in both groups. Uptake was half-maximally stimulated by 32.5 +/- 8.1 mmol/L sodium in controls and 41.4 +/- 6.2 mmol/L sodium in treated animals. These results indicate that within 24 h methylprednisolone suppressed intestinal sodium-coupled phosphate transport. This is due to decreased maximal transport capacity without changes in transporter affinity for phosphate or sodium.

Animals↗

Ontogeny of intestinal phosphate absorption in rabbits.

The ontogeny of intestinal phosphate transport was examined in brush-border membrane vesicles prepared from 2-wk, 4-wk, 6-wk, and 3-mo-old rabbits. At all four ages, vesicles prepared from the duodenum demonstrated sodium-phosphate cotransport in that uptake in the presence of a sodium gradient was significantly greater than uptake in the presence of a potassium gradient. While sodium-independent phosphate uptake was comparable at all ages, sodium-phosphate cotransport was greatest in the youngest animals and declined with increasing age. Peak phosphate uptake was 10-fold the equilibrium value at 2 wk and declined to 3-fold in adults. Maximal transport capacity of sodium-phosphate cotransport fell from 2,292 +/- 161 at 2 wk to 286 +/- 12 pmol.mg-1.10 s-1 at 3 mo, whereas the Michaelis constant did not change with age, varying between 0.032 and 0.054 mM. At all ages, uptake was half-maximally stimulated between 30 and 50 mM sodium, and Hill coefficients were between 1.5 and 2. Generation of inside negative diffusion potentials did not significantly enhance phosphate uptake at any age. These data suggest that throughout development, the transport of each phosphate molecule across the rabbit duodenal brush-border membrane is coupled to the transport of two sodium molecules. There were distinct developmental changes in the distribution of the sodium-phosphate cotransport along the length of intestine. In 2-wk old animals, sodium-phosphate cotransport was present in the duodenum, proximal and distal jejunum, and proximal ileum. In 4-wk-old animals, sodium-phosphate cotransport was present throughout the duodenum and proximal and distal jejunum, and in 6-wk and 12-wk-old animals, sodium-phosphate cotransport was observed only in the duodenum and proximal jejunum.

Absorption↗

Modulation of EGF-receptors by phorbol ester in small intestinal crypt cells.

We have previously shown that EGF promotes growth and proliferation of enterocytes isolated from the crypts of the rat small intestine (IEC-6). In the present studies we have measured the affinity of EGF for its receptor, and estimated the number of surface EGF receptors on IEC-6 cells. Scatchard analysis indicates IEC-6 cells display 45,000 EGF receptors per cell with a dissociation constant of 41 pM. Treatment with phorbol-12-myristate-13-acetate (PMA) results in a dose-dependent inhibition of cell growth which is paralleled by reduced binding of 125I-EGF. Incubation of IEC-6 cells with 10 nM PMA results in a 70 percent decrease in the number of EGF receptors without a significant change of receptor affinity (kd 68 pM vs 41 pM). PMA treatment is also associated with a significant increase of protein kinase-C activity in IEC-6 cells. The reciprocal relationship between protein kinase-C activation and EGF receptors suggests in this cell line of crypt enterocytes, protein kinase-C may inhibit cellular proliferation by modulating EGF receptors.

Animals↗