M. Di Rocco

Winchester syndrome caused by a homozygous mutation affecting the active site of matrix metalloproteinase 2

The inherited osteolysis syndromes are a heterogeneous group of skeletal disorders whose classification is still uncertain. Three osteolysis syndromes show autosomal recessive inheritance and multicentric involvement: Torg syndrome (OMIM 259600), Winchester syndrome (OMIM 277950) and Nodulosis–Arthropathy–Osteolysis syndrome (NAO; OMIM 605156). The 2001 Nosology of the International Skeletal Dysplasia Society (Hall CM, Am J Med Genet 2002: 113: 65) classifies NAO as a variant of Torg syndrome, while Winchester syndrome is considered as a separate disorder. Recently, mutations in the matrix metalloproteinase 2 (MMP2) gene were identified in affected individuals with a clinical diagnosis of NAO in two Arab families. We report a homozygous missense mutation (E404K) in the active site of MMP2 in a 21‐year‐old woman with a severe form of osteolysis best compatible with a diagnosis of Winchester syndrome. The clinical and molecular findings suggest that Torg, NAO and Winchester syndromes are allelic disorders that form a clinical spectrum.

Arg113His mutation in eIF2B as cause of leukoencephalopathy in adults

Vanishing white matter is a leukoencephalopathy that usually affects young children. Five genes were found recently for this disease, allowing a DNA-based diagnosis. The authors describe six patients homozygous for the Arg113His mutation in eIF2Bε. Only one had a childhood onset; four had a later onset and a protracted disease course; one adult still has no symptoms. Our data suggest that the Arg113His mutation is particularly mild and should be considered in the differential diagnosis of adult diffuse leukoencephalopathies, independent of whether there are associated clinical signs, an episodic course, or MRI shows white matter rarefaction/cystic degeneration.

Mutations in Cytokine Receptor-Like Factor 1 (CRLF1) Account for Both Crisponi and Cold-Induced Sweating Syndromes

Crisponi syndrome is a rare autosomal recessive disorder characterized by congenital muscular contractions of facial muscles, with trismus in response to stimuli, dysmorphic features, bilateral camptodactyly, major feeding and respiratory difficulties, and access of hyperthermia leading to death in the first months of life. The overlap with Stuve-Wiedemann syndrome (SWS) is striking, but the two conditions differ in that congenital lower limb bowing is absent in Crisponi syndrome, whereas it is a cardinal feature of SWS. We report here the exclusion of the leukemia inhibitory factor receptor gene in Crisponi syndrome and the identification of homozygote or compound heterozygote cytokine receptor-like factor 1 (CRLF1) mutations in four children from three unrelated families. The four mutations were located in the immunoglobulin-like and type III fibronectin domains, and three of them predicted premature termination of translation. Using real-time quantitative polymerase chain reaction, we found a significant decrease in CRLF1 mRNA expression in patient fibroblasts, which is suggestive of a mutation-mediated decay of the abnormal transcript. CRLF1 forms a heterodimer complex with cardiotrophin-like cytokine factor 1, and this heterodimer competes with ciliary neurotrophic factor for binding to the ciliary neurotrophic factor receptor (CNTFR) complex. The identification of CRLF1 mutations in Crisponi syndrome supports the key role of the CNTFR pathway in the function of the autonomic nervous system.

Glycogen storage disease: recommendations for treatment.

A workshop was held on “Aspects of treatment of patients with glycogen storage disease” within the framework of the Concerted Action “Inborn errors of metabolism” of the European Communities. Consensus was reached on the main issues of treatment of patients with deficiency of glucose-6-phosphatase, glucose-6-phosphate translocase, debranching enzyme, liver phosphorylase and phosphorylase-b-kinase. The resulting recommendations are reported.

Arthrogryposis, renal dysfunction and cholestasis syndrome: report of five patients from three Italian families

We report on five patients from three families with neurogenic arthrogryposis, cholestasis and tubular renal dysfunction. Despite a similar clinical picture the liver histology showed a broad pathological spectrum, ranging from pigment storage to parenchymal giant cell transformation and ductopenia. The findings are compared with those of other cases from the literature in search of a correct nosology of the syndrome characterized by arthrogryposis, renal and liver disease.ConclusionWe propose to consider the picture of arthrogryposis, renal tubular dysfunction and cholestasis as a single syndrome.

Neutropenia and impaired neutrophil function in glycogenosis type Ib

The impairment of different neutrophil functions has recently been reported in some patients with glycogenosis Ib and neutropenia. However, no satisfactory explanation for these findings has so far been supplied. In order to investigate this problem, we have studied neutrophil functions (random locomotion and chemotaxis, O2− release, [1-14C]glucose oxidation and cellular cytotoxicity) in two further patients with glycogenosis Ib and neutropenia. The results show that neutrophil dysfunctions related to the involvement of both hexose monophosphate shunt and anaerobic glycolysis were variable. The heterogeneity of neutrophil functional impairment in glycogenosis Ib and their possible relationship with the basic metabolic defect of the disease are discussed.

Leukoencephalopathy with vanishing white matter:: an adult onset case.

Leukoencephalopathy with vanishing white matter (VWM) is an autosomal recessive disorder also known as childhood ataxia with central hypomyelination (CACH). Typically, the onset is in late infancy or early childhood with spasticity, cerebellar ataxia, and a relatively mild mental impairment.1 The course is chronic progressive with episodes of rapid deterioration after infection and minor head trauma. MRI shows a diffuse abnormality of the cerebral white matter with variable cerebellar atrophy mainly affecting the vermis. With time, there is evidence of white matter rarefaction leading to cystic degeneration. Increasing portions of the cerebral white matter vanish …

Efficacy of ACE‐inhibitor therapy on renal disease in glycogen storage disease type 1: a multicentre retrospective study

Background  The efficacy of ACE‐inhibitors in decreasing microalbuminuria and proteinuria has been reported in a few patients with glycogen storage disease type 1 (GSD1); however, no case‐control study has ever been published.

Pontocerebellar hypoplasia: Clinical, pathologic, and genetic studies

Background: Mutations in genes encoding subunits of the tRNA-splicing endonuclease (TSEN) complex were identified in patients with pontocerebellar hypoplasia 2 (PCH2) and pontocerebellar hypoplasia 4 (PCH4). Objective: We report molecular genetic findings in 12 Italian patients with clinical and MRI findings compatible with PCH2 and PCH4. Methods: We retrospectively selected a cohort of 12 children from 9 Italian families with MRI of hypoplastic pontocerebellar structures and clinical manifestations suggesting either PCH2 or PCH4 and submitted them to direct sequencing of the genes encoding the 4 subunits of the TSEN complex, namely TSEN54, TSEN34, TSEN15, and TSEN2. Results: In a cohort of 12 children, we detected the common p.A307S mutation in TSEN54 in 9/12 available patients from nine unrelated families. We also detected a novel c.1170_1183del (p. V390fs39X) in compound heterozygosity with the common p.A307S in a child with a severe PCH4 phenotype. In another severely affected patient, the second mutant allele was not identified. Two sibs without mutations in the TSEN complex were unlinked to the PCH3 locus. In addition to typical clinical and neuroradiologic features of PCH2, both children were affected by a tubulopathy resembling Bartter syndrome. Conclusions: We confirm that the common p.A307S mutation in TSEN54 is responsible for most of the patients with a PCH2 phenotype. The presence of a heterozygous in/del variant correlates with a more severe phenotype as PCH4. In addition, we describe a new clinical form of PCH in 2 sibs with clinical and MRI features of PCH2.

Long-term survival in Stuve-Wiedemann syndrome: A neuro-myo-skeletal disorder with manifestations of dysautonomia

Stuve‐Wiedemann syndrome (SWS) is a multiple congenital anomalies syndrome mostly considered to have an early lethality. Only few patients have been reported with long survival; therefore, the clinical phenotype with age has not yet been clearly characterized. We report on two patients with SWS aged 12 and 3 years who have both the osteodysplastic symptoms of the entity as well as autonomic nervous system symptoms resembling familial dysautonomia: lack of corneal reflex and neuropathic keratitis, absence of fungiform papillae, ulcerations of the tongue, paradoxical sweating at low temperature, patellar hyporeflexia, and progressive scoliosis. The clinical and radiological similarities between patients with SWS and patients with Schwartz‐Jampel syndrome have led to the suggestion that these two syndromes are a single entity. SWS and Schwartz‐Jampel syndrome type II are now indeed considered to be identical, but the radiographic phenotype of SWS long survivors such as the presently reported patients justifies the distinction between SWS and the classical type of Schwartz‐Jampel syndrome. An increased number of lipid droplets in muscle fibers and decreased muscle mitochondrial enzyme activities have been found in one patient, confirming a previously reported association between SWS and respiratory chain abnormalities.