Spectrum of mutations in the renin-angiotensin system genes in autosomal recessive renal tubular dysgenesis.

Autosomal recessive renal tubular dysgenesis (RTD) is a severe disorder of renal tubular development characterized by early onset and persistent fetal anuria leading to oligohydramnios and the Potter sequence, associated with skull ossification defects. Early death occurs in most cases from anuria, pulmonary hypoplasia, and refractory arterial hypotension. The disease is linked to mutations in the genes encoding several components of the renin-angiotensin system (RAS): AGT (angiotensinogen), REN (renin), ACE (angiotensin-converting enzyme), and AGTR1 (angiotensin II receptor type 1). Here, we review the series of 54 distinct mutations identified in 48 unrelated families. Most of them are novel and ACE mutations are the most frequent, observed in two-thirds of families (64.6%). The severity of the clinical course was similar whatever the mutated gene, which underlines the importance of a functional RAS in the maintenance of blood pressure and renal blood flow during the life of a human fetus. Renal hypoperfusion, whether genetic or secondary to a variety of diseases, precludes the normal development/ differentiation of proximal tubules. The identification of the disease on the basis of precise clinical and histological analyses and the characterization of the genetic defects allow genetic counseling and early prenatal diagnosis.

Severe bullous skin lesions associated with Chikungunya virus infection in small infants.

INTRODUCTION: The aim of this study was to describe a pediatric case series of Chikungunya infection associated with extensive bullous skin lesions, a severe and unknown form of the disease, during the 2005-2006 outbreak in La Réunion Island. MATERIALS AND METHODS: Retrospective descriptive hospital-based study in children presenting blisters > or = 10% of total body surface area with laboratory-confirmed Chikungunya infection. RESULTS: Eight boys and five girls with a mean age of 3.4 months were included. Blistering began after an average of 2 days after onset of fever and affected 21.5% (10% to 35%) of the total body surface area. Reverse transcription-polymerase chain reaction of blister fluid (n = 5) was positive with a mean viral load sometimes higher than in concurrent serum. Histopathologic examination (n = 10) showed intraepidermal blisters. Hospitalization and repeated dressing changes under general anesthesia were required. No death occurred. On follow-up, long term repigmentation was excellent with sometimes cosmetic sequelae. CONCLUSION: Chikungunya should be included in the differential diagnosis of febrile blistering dermatoses in small infants in epidemic areas.

Rapidly growing mature retroperitoneal teratomas.

Retroperitoneal mature teratomas are rare benign tumors, most commonly found in neonates and young adults. We report 2 cases of fast-growing retroperitoneal mature teratomas. Both patients were girls operated on before the age of 6 months. In both cases, during the delay between diagnosis and surgery, the tumors practically doubled in size every 10 days. We believe the possibility of rapid growth of these tumors implies that treatment should be conducted as soon as possible.

Perlman syndrome: report, prenatal findings and review.

Perlman syndrome is a rare overgrowth syndrome characterized by polyhydramnios with neonatal macrosomia, nephromegaly, distinctive facial appearance, renal dysplasia, nephro-blastomatosis, and predisposition to Wilms tumor (WT). We report on a newborn with prenatal sonographic signs of Perlman syndrome, large fetal ascites, nephromegaly and macrosomia. The clinical course was marked by neonatal distress, renal failure and refractory hypoxemia leading to death at 2 days of life. Renal histologic examination showed bilateral nephroblastomatosis. Genetic or epigenetic alterations of the 11p15 region (involved in the BWS), including mutation of the CDKN1C gene were excluded. No mutation of the GPC3 gene was identified. We review the 28 patients who have been reported with Perlman syndrome. The prognosis of Perlman syndrome is poor with a high neonatal mortality rate. Among the infants who survived beyond the neonatal period, 64% developed a WT and all had a developmental delay. Fetal macrosomia, ascites and polyhydramnios are frequent manifestations. Clinical overlaps with other overgrowth syndromes particularly Beckwith-Wiedemann syndrome and Simpson-Golabi-Behmel syndrome have been emphasized. Perlman syndrome is considered as an autosomal recessive condition. We review 19 patients from seven sibships with parental consanguinity in two families only. The other cases were sporadic. The 28 reported patients had only 10 unaffected sibs. The low percentage of consanguinity among parents is also puzzling for a rare recessive condition. The molecular basis of Perlman syndrome is unknown. (Epi)genetic anomalies of 11p15 and mutations in GPC3 were not studied in most of the previous reports.

Pulmonary alveolar proteinosis in children on La Réunion Island: a new inherited disorder?

BACKGROUND: Pulmonary alveolar proteinosis (PAP) is very rare in children. Only a few small series have been published, with little information about long-term progression. The objective of our study was to describe the clinical, radiological and pathological features, and the long-term course of PAP in a cohort of 34 children from La Réunion Island. METHODS: Data were retrospectively collected from medical files. Radiological and pathological elements were reviewed by two pediatric radiologists and three pathologists, respectively. RESULTS: Thirteen cases were familial and 32/34 (94%) cases were family connected. Disease onset occurred in the first six months of life in 82% of the patients. Thoracic computed tomography scans showed the typical "crazy-paving" pattern in 94% of cases. Respiratory disease was associated with a liver disorder, with the detection of liver enlargement at diagnosis in 56% of cases. The course of the disease was characterized by frequent progression to chronic respiratory insufficiency, accompanied by the appearance of cholesterol granulomas and pulmonary fibrosis. Overall prognosis was poor, with a mortality of 59% and an overall five-year survival rate from birth of 64%. Whole-lung lavages were performed in 21 patients, with no significant effect on survival. Liver disease progressed to cirrhosis in 18% of children, with no severe complication. CONCLUSIONS: PAP in children from la Réunion Island is characterized by an early onset, associated liver involvement, poor prognosis and frequent progression to lung fibrosis, despite whole-lung lavages treatment. The geographic clustering of patients and the detection of many familial links between most of the cases strongly suggest a genetic etiology, with an autosomal recessive mode of inheritance.

Breast metastasis of a squamous cell carcinoma of the uterine cervix mimicking inflammatory breast cancer.

Breast metastases from distant carcinoma are infrequent, and cervix carcinoma is rarely the primary lesion. We describe the first case of a cervical squamous cell carcinoma with breast metastasis mimicking an inflammatory breast cancer in a 74-year-old woman. Seventeen months after the treatment of a primary tumor, the patient developed breast lesions looking like an inflammatory breast tumor. After a 1-year delay due to the patient's refusal, pathological examination and immunohistochemistry confirmed the diagnosis of breast metastasis from a poorly differentiated squamous cell carcinoma. The volume of the breast was huge, associated with axillary lymphadenopathies and multiple lung metastases. Despite platinum-based chemotherapy, the disease progressed and the patient died rapidly, 3 months after the first chemotherapy cycle and 15 months after the first mammary symptoms. We review the literature concerning breast metastases from gynecologic cancers and, particularly, from cervical squamous cell carcinoma. Differential diagnosis of such lesions may be problematic but is essential to avoid unnecessary mutilating surgery and to institute the appropriate systemic therapy. The prognosis is poor.

Multicentric Castleman disease in an HHV8-infected child born to consanguineous parents with systematic review.

Childhood multicentric Castleman disease (MCD) is a rare and unexplained lymphoproliferative disorder. We report a human herpesvirus-8 (HHV-8)-infected child, born to consanguineous Comorian parents, who displayed isolated MCD in the absence of any known immunodeficiency. We also systematically review the clinical features of the 32 children previously reported with isolated and unexplained MCD. The characteristics of this patient and the geographic areas of origin of most previous cases suggest that pediatric MCD is associated with HHV-8 infection. Moreover, as previously suggested for Kaposi sarcoma, MCD in childhood may result from inborn errors of immunity to HHV-8 infection.

Human muscle satellite cells as targets of Chikungunya virus infection.

BACKGROUND: Chikungunya (CHIK) virus is a mosquito-transmitted alphavirus that causes in humans an acute infection characterised by fever, polyarthralgia, head-ache, and myalgia. Since 2005, the emergence of CHIK virus was associated with an unprecedented magnitude outbreak of CHIK disease in the Indian Ocean. Clinically, this outbreak was characterized by invalidating poly-arthralgia, with myalgia being reported in 97.7% of cases. Since the cellular targets of CHIK virus in humans are unknown, we studied the pathogenic events and targets of CHIK infection in skeletal muscle. METHODOLOGY/PRINCIPAL FINDINGS: Immunohistology on muscle biopsies from two CHIK virus-infected patients with myositic syndrome showed that viral antigens were found exclusively inside skeletal muscle progenitor cells (designed as satelllite cells), and not in muscle fibers. To evaluate the ability of CHIK virus to replicate in human satellite cells, we assessed virus infection on primary human muscle cells; viral growth was observed in CHIK virus-infected satellite cells with a cytopathic effect, whereas myotubes were essentially refractory to infection. CONCLUSIONS/SIGNIFICANCE: This report provides new insights into CHIK virus pathogenesis, since it is the first to identify a cellular target of CHIK virus in humans and to report a selective infection of muscle satellite cells by a viral agent in humans.

Inflammatory pseudotumor of the ureter.

Inflammatory myofibroblastic pseudotumors are rare solid tumors found in most soft tissue locations although mainly in the lung. Their etiology is uncertain, and they are generally considered benign although some have a potential for recurrence and dissemination. Recent studies have suggested, however, that some of these tumors are in fact neoplastic processes that harbor chromosomal aberrations similar to those seen in certain lymphomas. The authors report a case of inflammatory pseudotumor of the ureter in a child and discuss recent reports.