Faculty Bibliography

OBJECTIVE: To report and propose a consensus term for eight cases of a newly recognized, asymptomatic, rapidly growing unilateral labium majus mass without palpable borders in prepubertal girls, appearing to be temporally associated with the physiologic increase of adrenal hormones. METHODS: Histologic examination, special stains, and immunohistochemistry were performed on all cases. In our personal cases, electron microscopy and chromosomal analysis were also performed, together with pelvic magnetic resonance imaging (MRI), inguinal exploration, vaginoscopy with biopsies, and adrenal hormone levels. RESULTS: Of the eight cases, seven were Ashkenazi Jewish girls from the same area in New York City. The unilateral masses were asymptomatic, soft, without palpable borders. The overlying skin had a slightly tan peau d'orange surface. The masses could not be completely excised because they extended into the contiguous pelvic floor. Histologically, the masses were composed of bland hypocellular fibrous tissue extending into the deep subcutaneous tissue. The masses blended into the surrounding tissue and adjacent pelvic floor as shown by MRI preoperatively and postoperatively. Residual tissue did not progress after incomplete resection. CONCLUSION: These fibrous lesions develop in months at the time of physiologic increase in adrenal hormone secretion just before puberty and subsequently appear to stop growing. The surgeon should not attempt a complete removal but simply excise sufficient tissue for a reasonable cosmetic result and to confirm the diagnosis. The lesions reflect fibroblastic hyperplasia, which is possibly hormone-driven. The ethnic and geographic clustering of cases raises consideration of environmental exposures or genetic predisposition

BACKGROUND & AIMS: Ileal bile acid malabsorption is present in Crohn's ileitis. The molecular mechanisms of regulation of the apical sodium-dependent bile acid transporter (ASBT) by inflammatory cytokines in vitro and in vivo are investigated. METHODS: Transient transfection studies of the human, mouse, and rat ASBT promoters and Northern analyses were performed in cells treated with the inflammatory cytokines and/or various activator protein-1 constructs. Rat ASBT promoter transgenic, wild-type, and c-fos-null mice were treated with indomethacin to assess the response to acute inflammation of the ileal mucosa. RESULTS: In Caco-2 cells, ASBT messenger RNA expression was reduced 65% after interleukin-1beta treatment, while c-fos and c-jun were up-regulated 2-fold. Human ASBT promoter activity was enhanced by c-jun and repressed by a dominant negative c-jun, c-fos, or a dominant negative c-fos. Meanwhile, c-fos antisense treatment activated the human ASBT promoter 5-fold and not only abrogated interleukin-1beta-mediated repression but led to a paradoxical increase in ASBT promoter activity. Indomethacin-induced acute ileitis led to repression of ASBT in wild-type mice and in the transgenic rat ASBT promoter reporter, while paradoxical activation of ASBT was seen in c-fos-null mice. Indomethacin-induced ileal injury was greater in the c-fos-null mice compared with the wild-type littermates. CONCLUSIONS: Human, rat, and mouse ASBT is inhibited by inflammatory cytokines via direct interactions of c-fos with the ASBT promoter.

OBJECTIVES: A subset of patients with allergic eosinophilic gastroenteritis (AEG) has anemia and hypoalbuminemia caused by protein-losing enteropathy (PLE). Our goals were to describe the response to therapy and the long-term outcome of patients in this subgroup and to evaluate their gastric and intestinal biopsies for distinguishing features that might explain their protein and blood loss. METHODS: Patients with AEG + PLE were identified retrospectively and compared with controls and with patients with AEG only. Immunohistochemical staining for tryptase, a mast cell mediator, was performed on gastric and duodenal tissues. Eosinophils identified by hematoxylin/eosin stain and mast cells identified as tryptase-positive cells were counted in one high-power field area with maximal cell infiltration. RESULTS: Although all patients had excellent response to therapy with amino acid-based formula and tolerated gradual introduction of some foods with time, food-responsive disease persisted in all patients over 2.5 to 5.5 years of follow-up. Routine histological evaluation did not show any features differentiating AEG + PLE from AEG. When eosinophils and mast cells were counted in intestinal biopsies, however, significantly more mast cells were found in biopsies of the AEG + PLE group despite comparable numbers of eosinophils. In contrast, in gastric biopsies, eosinophils were more prominent in AEG + PLE, but mast cell numbers were similar in all groups. CONCLUSIONS: Patients with AEG + PLE responded well to therapy with amino acid-based formula. Food hypersensitivities did not completely resolve over up to 5.5 years. Intestinal mast cells were significantly increased in maximally infiltrated areas of the intestine, possibly causing increased intestinal permeability and protein loss.

Autosomal recessive polycystic kidney disease (ARPKD) is characterized by dilation of ectatic renal collecting ducts, intrahepatic biliary dysgenesis, and portal fibrosis. Portal hypertension and recurrent bacterial cholangitis can dominate the clinical picture in long-term survivors. Predominant extrahepatic bile duct disease was revealed in four patients who underwent magnetic resonance cholangiopancreatography. All four patients had portal hypertension, although liver biochemistries did not suggest biliary disease. In two of the patients, cholangitis was clinically ascribed to the bile duct disease. Western blot analysis of plasma membranes from normal rat extrahepatic bile duct and kidney revealed the presence of polyductin as a single approximately 440 kDa protein. Although the exact function of polyductin in the extrahepatic duct is unknown, it may have a role in the development and control of lumenal size. Clinical management of patients with ARPKD should include consideration of potential problems related to extrahepatic bile duct disease.

BACKGROUND: Toxoplasmosis prophylaxis is standard following heart and heart lung transplantation, when an increased risk of allograft transmitted Toxoplasma is well-recognized. In contrast, prophylaxis and routine serologic evaluation of donors and recipients for Toxoplasma in noncardiac solid organ transplantation (SOT) is not recommended. We report the first case of disseminated toxoplasmosis following small bowel transplantation, presumably transmitted via the transplanted intestine and systematically review reported cases of toxoplasmosis in noncardiac SOT recipients to determine if current guidelines should be reconsidered. METHODS: Systematic MEDLINE review was performed for tissue invasive toxoplasmosis in noncardiac SOT recipients and analysis of clinical features, serologic status, and treatment regimens with respect to mortality. RESULTS: Fifty-two cases of toxoplasmosis in noncardiac SOT recipients were identified. Eighty-six percent developed disease within 90 days of transplantation. Presentation was nonspecific and consisted of fever (77%), respiratory distress (29%), neurologic manifestations (29%), and bone marrow suppression (26%). Multivariate analyses demonstrated that localized disease (odds ratio [OR]=37.36, 95% CI 1.85-754.85), treatment received (OR=1.814, 95% CI 1.193-3.480) and donor and recipient serostatus (OR=1.39, 95% CI 1.068-1.815) were predictors of survival. High-risk recipients (donor seropositive/recipient seronegative) developed disease earlier (16 days vs. 31 days P=0.002) and were less likely to survive (OR=0.14, 95% CI 0.03-0.69) than standard-risk recipients. CONCLUSIONS: Toxoplasmosis is recognized following noncardiac SOT. Reduction of morbidity and mortality necessitates knowledge of donor and recipient Toxoplasma serostatus, prophylaxis, early diagnosis, and treatment. The findings support a reconsideration of pretransplantation evaluation and prophylaxis strategies in SOT recipients.

Hepatic complications occur in a significant proportion of children with autosomal recessive polycystic kidney disease (ARPKD). PKHD1/fibrocystin, the defective gene in ARPKD, is expressed in the cilia of bile duct epithelium and leads to abnormalities in the rubric of the ductal plate malformation. Portal hypertension and biliary disease are the major liver problems seen in ARPKD. Complete blood counting, physical examination, ultrasonography and magnetic resonance (MR) cholangiography are indicated as screening procedures for hepatic disease in ARPKD. Medical and surgical interventions are potentially indicated for children with portal hypertension and/or biliary disease. A high index of suspicion for the diagnosis of cholangitis needs to be maintained in children with biliary disease. The implications of hepatic disease need to be considered in the decision-making regarding renal transplantation in ARPKD.

The etiology of acute liver failure in children is unknown in a large number of cases. Defects in fatty acid oxidation have been shown to lead to severe liver injury. This retrospective analysis examined the bile acylcarnitine profiles of 27 children with acute liver failure who underwent liver transplantation or died. Results were compared with 758 postmortem samples from individuals without acute liver failure. Cumulative amounts of free carnitine, medium- or long-chain species in excess of the 95th percentile of the control group were considered abnormal. Fourteen samples had normal profiles. Three had markedly elevated concentrations of free carnitine, whereas ten showed elevations in medium- or long-chain species. The relative risk of death was 2.86 (95% confidence interval, 1.08-7.54, P = .01) in the 10 children with elevated concentrations of medium- or long-chain species compared with those with normal analyses. Overall, medium- and long-chain acylcarnitines were increased in those patients who died compared with survivors, (dead vs. alive; medium-chain, 187 +/- 74 vs. 32 +/- 12 micromol/L, P = .008; long-chain, 146 +/- 74 vs. 15 +/- 8 micromol/L, mean +/- standard error of the mean, P = .018). These studies describe biliary free and esterified carnitine profiles in children with acute liver failure. In conclusion, the findings raise the hypothesis that abnormalities in fatty acid oxidation may predispose to a worse outcome in acute liver failure.

OBJECTIVES: The human caliciviruses, which include Norwalk-like viruses (or Noroviruses) and Sapporo viruses, commonly cause epidemic and endemic viral gastroenteritis of short duration in healthy individuals. However, the impact of human calicivirus in immunosuppressed populations has not been established. The authors report five pediatric patients who developed human calicivirus enteritis after intestinal transplantation. METHODS: Infection was documented with repetitive reverse transcription polymerase chain reaction testing with nucleotide sequencing of tissue and lumen fluid specimens. RESULTS: A single strain, type Miami Beach, affected all patients in the hospital with an apparent index case. A potential mode of transmission was not defined. Severe osmotic or secretory diarrhea necessitated intravenous fluid therapy for 40 days or more in three of the five infants. Concurrent or recent subclinical allograft infection with adenovirus in two patients was associated with more severe symptoms. Virus excretion exceeded 80 days in two patients. Differentiation of human calicivirus enteritis from allograft rejection was difficult, as both disorders were associated with increased enterocyte apoptosis and inflammation. Intensification of immunosuppressive therapy because of suspected rejection appeared to prolong symptoms. CONCLUSION: These findings demonstrate that human calicivirus can be a significant pathogen in intestinal transplant recipients and potentially in other immunocompromised patients.