Loss of ß-catenin induces multifocal periosteal chondroma-like masses in mice.

Osteochondromas and enchondromas are the most common tumors affecting the skeleton. Osteochondromas can occur as multiple lesions, such as those in patients with hereditary multiple exostoses. Unexpectedly, while studying the role of ß-catenin in cartilage development, we found that its conditional deletion induces ectopic chondroma-like cartilage formation in mice. Postnatal ablation of ß-catenin in cartilage induced lateral outgrowth of the growth plate within 2 weeks after ablation. The chondroma-like masses were present in the flanking periosteum by 5 weeks and persisted for more than 6 months after ß-catenin ablation. These long-lasting ectopic masses rarely contained apoptotic cells. In good correlation, transplants of ß-catenin-deficient chondrocytes into athymic mice persisted for a longer period of time and resisted replacement by bone compared to control wild-type chondrocytes. In contrast, a ß-catenin signaling stimulator increased cell death in control chondrocytes. Immunohistochemical analysis revealed that the amount of detectable ß-catenin in cartilage cells of osteochondromas obtained from hereditary multiple exostoses patients was much lower than that in hypertrophic chondrocytes in normal human growth plates. The findings in our study indicate that loss of ß-catenin expression in chondrocytes induces periosteal chondroma-like masses and may be linked to, and cause, the persistence of cartilage caps in osteochondromas.

Renal-hepatic-pancreatic dysplasia: a sibship with skeletal and central nervous system anomalies and NPHP3 mutation.

We report on five consecutive sibs three with fatal renal-hepatic-pancreatic dysplastic (RHPD) syndrome and two pregnancies ending in early abortion. Three of the fetuses reached term and two survived for 15 and 58 days. They had diffusely cystic kidneys with absence of the distal collecting tubules, hepatic fibrosis, bile duct paucity, and pancreatic fibrosis with irregularly dilated ducts. These findings correspond to many of those reported by Ivemark et al. [Ivemark et al. (1959); Acta Paediat Scand 48: 1-11] as part of the RHPD syndrome. There are several notable differences in this family: one patient had hypocalvaria and a choroid plexus cyst at the right foramen of Luschka, multiple bone abnormalities including widened growth plates and abnormal development of the trabeculae of the ribs, "handle-bar" clavicles, wedge defects of the inferior margin of several thoracic vertebrae; the second patient had hypocalvaria and abnormally developed brain with bilateral exposure of the insulae; and a third patient had anencephaly. Mutational analysis of the two who survived beyond post-delivery demonstrated compound heterozygous novel frameshift mutations in the nephronophthisis type 3 gene (NPHP3).

Atypical glomerulopathy associated with the cblE inborn error of vitamin B12 metabolism.

BACKGROUND: The cblE disorder is an inherited disorder of vitamin B12 metabolism that results in elevated levels of homocysteine and decreased methionine in body fluids. Renal complications have been reported in patients with cblC disease, but not in those with cblE disease. The renal complications of cblC disease include thrombotic microangiopathy (TMA), neonatal hemolytic uremic syndrome, chronic renal failure, tubulointerstitial nephritis and proximal renal tubular acidosis. Previously, we reported a patient with cblC disease who had an atypical glomerulopathy that manifested with proteinuria and progressive renal insufficiency. CASE-DIAGNOSIS/TREATMENT: Studies were done on cultured fibroblasts. Renal biopsy tissue was examined by light and electron microscopy. There was decreased incorporation of labeled methyltetrahydrofolate and decreased synthesis of methylcobalamin. Complementation analysis placed the patient into the cblE complementation group. The findings from the histological and ultrastructural studies of renal biopsy were similar, but not identical, to those of idiopathic membranoproliferative glomerulonephritis (MPGN) and overlapped with those of TMA. CONCLUSIONS: We describe a patient with cblE disease who had an atypical glomerulopathy similar to MPGN. Additional findings included migraine headaches, hypothyroidism and livedo reticularis.

Survival in primary congenital pulmonary lymphangiectasia with hydrops fetalis.

The recent advances in neonatal and pediatric intensive care have changed the outcome of patients with congenital pulmonary lymphangiectasia of different types, including those cases with early neonatal symptoms. However, the patients who present the most severe form of the disease, manifested by in utero hydrops (including those treated by in utero thoracoamniotic shunting to relieve the mediastinal compression), have had an unvaryingly fatal ending in all published reports, with most cases dying before birth, and the few born alive dying during the first days of life. We present a patient with primary congenital pulmonary lymphangiectasia complicated by hydrops fetalis, who was treated in utero, survived the neonatal period after intensive medical and surgical support, and was discharged home at the age of 2 months. She is currently 6 months old, and has minimal signs or symptoms of chronic lung disease. The different aspects of the management of congenital pulmonary lymphangiectasia are discussed in this report, together with a review of the literature.

Primary pigmented nodular adrenocortical disease reveals insulin-like growth factor binding protein-2 regulation by protein kinase A.

OBJECTIVE: Primary pigmented nodular adrenocortical disease (PPNAD) can occur as an isolated trait or part of Carney complex, a familial lentiginosis-multiple endocrine neoplasia syndrome frequently caused by mutations in PRKAR1A, which encodes the 1alpha regulatory subunit of protein kinase A (PKA). Because alterations in the insulin-like growth factor (IGF) axis, particularly IGF-II and IGF binding protein (IGFBP)-2 overexpression, have been implicated in sporadic adrenocortical tumors, we sought to examine the IGF axis in PPNAD. DESIGN: RNA samples and paraffin-embedded sections were procured from adrenalectomy specimens of patients with PPNAD. Changes in expression of IGF axis components were evaluated by real-time quantitative RT-PCR and immunohistochemistry. NCI-H295R cells were used to study PKA and IGF axis signaling in adrenocortical cells in vitro. RESULTS: IGFBP-2 mRNA level distinguished between the two genetic subtypes of this disease; increased IGFBP-2 expression in PRKAR1A mutation-positive PPNAD tissues was also confirmed by immunohistochemistry. Moreover, PKA inhibitors increased IGFBP-2 expression in NCI-H295R adrenocortical cells, and anti-IGFBP-2 antibody reduced their proliferation. CONCLUSIONS: IGFBP-2 expression is increased in PPNAD caused by PRKAR1A mutations, and in adrenocortical cancer cells. This is the first evidence for PKA-dependent regulation of IGFBP-2 expression in adrenocortical cells.

Ectopic salivary tissue of the tonsil: a case report.

To report one patient with an ectopic salivary tissue tag on the tonsil, and review the embryology, management, and implications of this benign disorder. Case report with literature review. Ectopic salivary tissue presented on the tonsil of a child as a painless, growing, unilateral pale exophytic mass. Tonsillectomy was performed to provide diagnosis, and was curative. Ectopic salivary tissue of the tonsil is a rare finding. Tonsillectomy allows for definitive diagnosis and treatment.

Comparison of labial minor salivary gland biopsies from childhood Sjögren syndrome and age-matched controls.

OBJECTIVE: To determine an appropriate focus score cutoff for childhood Sjögren syndrome (SS). METHODS: Labial salivary gland tissue from specimens from children with SS and age-matched controls was retrospectively identified and reviewed by a blinded oral pathologist. RESULTS: The presence of any focal sialadenitis (focus score > 0 foci/4 mm(2)) was common among childhood SS samples but present in only 1 of 8 control samples. CONCLUSION: The presence of any focal lymphocytic sialadenitis in minor labial salivary gland tissue is suggestive of childhood SS and should be included in future childhood SS-specific diagnostic or classification criteria.

Hepatic pathology may develop before the Fontan operation in children with functional single ventricle: an autopsy study.

OBJECTIVE: Liver fibrosis has emerged as an important long-term complication of the Fontan operation. We aimed to describe liver histology at autopsy in patients who had undergone the Fontan operation and to determine whether patient variables are associated with the degree of fibrosis. METHODS: A review was performed of all patients with a history of the Fontan operation who died and underwent autopsy at our institution from 1980 to 2009. Autopsy liver slides were evaluated independently by 2 pathologists. RESULTS: Twenty-two patients were studied. The median interval between Fontan and death was 20 days (range, 1 day-17.5 years). Portal fibrosis was observed in 20 (91%) patients and sinusoidal fibrosis was observed in 17 (77%) patients. Using simple linear regression, time from the Fontan operation was significantly associated with the degree of portal fibrosis on Ishak (P = .03) and modified Scheuer fibrosis (P = .02) scales. Significant portal fibrosis was observed in 8 (57%) of the 14 patients who died 30 days or less after the Fontan operation. In these 14 patients, severity of portal fibrosis was associated with length of hospitalization after pre-Fontan cardiac operations (P = .03) and pre-Fontan mean right atrial pressure (P = .04). CONCLUSIONS: At autopsy, hepatic fibrosis was commonly observed in patients who had undergone the Fontan operation. Portal fibrosis has been previously unrecognized in this population. Significant portal fibrosis occurred in most who died soon after the Fontan procedure and was associated with pre-Fontan morbidity. Hepatic disease in the single-ventricle population is multifactorial and may begin before the Fontan operation.

Diagnosis and treatment of pediatric vallecular cysts and pseudocysts.

OBJECTIVE: To review the experience at a children's hospital diagnosing and treating vallecular cysts. SECONDARY OBJECTIVES: To determine if cyst type, operative mode, or ages are risk factor(s) for recurrence. METHODS: Chart review of eleven children with vallecular cysts and pseudocysts from 1997 to 2009. RESULTS: The most common presenting symptoms were stridor (8/12, 67%), respiratory distress (7/12, 58%), and feeding difficulties (4/12, 33%). Symptoms of gastroesophageal reflux disease were present in 67% of patients and 17% carried a concurrent diagnosis of laryngomalacia. Eleven of twelve patients required operative intervention, the majority of which were transoral endoscopic procedures. Three patients (3/11, 27%) had recurrences. Two of these patients required only a second procedure, but one patient required multiple procedures. Fifty percent (2/4) of the patients 2 years or older experienced a recurrence, whereas only 14% (1/7) of the patients less than 2 years old had a recurrence, a difference which was not statistically significant (p=0.49). Pseudocysts tended to recur more frequently than vallecular cysts. (p=0.13). Surgical approach (marsupialization versus total excision) did not affect recurrence rate. One patient with a small, asymptomatic cyst was observed and continues to be symptom-free. There were no surgical complications. CONCLUSIONS: Vallecular cysts and pseudocysts are rare congenital lesions of the upper aerodigestive tract. Vallecular pseudocysts tended to recur more than vallecular cysts in our series. Surgery is the treatment of choice for symptomatic patients; smaller cysts may be followed closely.

Tissue-specific deletion of the coxsackievirus and adenovirus receptor protects mice from virus-induced pancreatitis and myocarditis.

In cultured cells, infection by group B coxsackievirus (CVB) is mediated by the coxsackievirus and adenovirus receptor (CAR), but the importance of this molecule in CVB-induced disease has not been determined. We generated mice with tissue-specific ablation of CAR within each of two major CVB target organs, the pancreas and heart. In the pancreas, deletion of CAR resulted in a significant reduction in both virus titers and virus-induced tissue damage. Similarly, cardiomyocyte-specific CAR deletion resulted in a marked reduction in virus titer, infection-associated cytokine production, and histopathology within the heart. Consistent with the in vivo phenotype, CAR-deficient cardiomyocytes resisted infection in vitro. These results demonstrate a critical function for CAR in the pathogenesis of CVB infection in vivo and in virus tropism for the heart and pancreas.

Lumbar puncture and surgical intervention in a child with undiagnosed fibrodysplasia ossificans progressiva.

Fibrodysplasia ossificans progressiva (FOP) is a rare, autosomal dominant disorder characterized by congenital malformation of the great toes and episodes of soft tissue swelling that lead to progressive heterotopic ossification. The genetic cause of FOP was recently discovered to be a recurrent missense activating mutation in the activin A type I receptor, a bone morphogenetic protein type I receptor in all classically affected individuals worldwide. The authors present a child with the classic features of previously undiagnosed FOP who developed a paraspinal soft-tissue mass after a lumbar puncture for a fever workup. Excision of the mass resulted in a massive inflammatory response leading to progression of heterotopic ossification. Awareness of the classic clinical features of FOP prior to the appearance of heterotopic ossification can prompt early clinical diagnosis and confirmation through genetic testing, thus avoiding interventions that lead to irreversible iatrogenic harm.

Renin-angiotensin axis blockade reduces proteinuria in presymptomatic patients with familial FSGS.

Familial and genetic forms of focal segmental glomerulosclerosis (FSGS) are associated with six different mutations in genes affecting the podocyte (NPHS2, ACTN4, CD2AP, WT1, TRPC6, and PLCE1). Immunosuppressive agents are often unsuccessful in treating this condition. Data regarding the efficacy of renoprotection through blockage of the renin-angiotensin axis is lacking. We describe three children from two different families with familial FSGS in whom partial to complete remission of proteinuria was attained through early blockade of the renin-angiotensin axis. In addition, there was no deterioration of renal function. We speculate that presymptomatic patients with normal renal function who have genetic or familial FSGS may benefit from early blockade of the renin-angiotensin axis and that this may also prevent progressive renal disease.

Multiple endocrine neoplasia type 2A in a kindred with C634Y mutation.

Multiple endocrine neoplasia type 2A (MEN 2A) is most frequently caused by codon 634 activating mutations. Medullary thyroid carcinoma has occurred before the age of 2, with pheochromocytomas and primary hyperparathyroidism occurring later in childhood. We report cases of 4 siblings with C634Y-positive MEN 2A (all <11 years old): 3 with medullary thyroid carcinoma (1 had nodal metastasis, and another had a parathyroid adenoma) and 1 with C-cell hyperplasia.

Cobalamin C deficiency complicated by an atypical glomerulopathy.

Cobalamin C (cbl C) deficiency, an inherited disorder of vitamin B12 metabolism, causes elevated levels of methylmalonic acid and homocysteine and decreased methionine in all body fluids. Renal complications of cbl C disease are thrombotic microangiopathy (TMA), chronic renal failure, tubulointerstitial nephritis and proximal renal tubular acidosis. There is, however, only one case report of primary glomerular pathology, focal segmental glomerulosclerosis, in a cbl C deficient patient. We report a case of an atypical glomerulopathy in a 16-year-old male patient with cbl C deficiency. The glomerulopathy manifested with proteinuria and progressive renal insufficiency. The renal histologic, immunofluorescent and ultrastructural findings were similar, but not identical, to idiopathic membranoproliferative glomerulonephritis (MPGN) but also overlapped with those of a TMA. The serum complement profile was normal; there were scanty glomerular deposits of C3, no deposits of IgG and ultrastructural findings that were similar to those seen in either MPGN type III or a TMA. On the basis of these findings we have designated the renal disease as an atypical glomerulopathy.

Factitious fungus in two children with cancer receiving liposomal amphotericin.

Amphotericin B deoxycholate and liposomal formulations of amphotericin are often started and continued empirically, in immunocompromised hosts, based on the computed tomography findings and the patient's clinical picture. The authors describe two patients with presumed fungal pulmonary nodules, which were progressive despite prolonged treatment with liposomal amphotericin B. At subsequent biopsy, neither had evidence of active fungal disease; rather, the nodules revealed reactive changes and lipid-laden macrophages. These cases underscore the importance of establishing a microbiologic diagnosis in cases of presumed fungal infection.