PIGQ-Related Glycophosphatidylinositol Deficiency Associated with Nonprogressive Congenital Ataxia

The glycophosphatidylinositol (GPI) anchor pathway plays an essential role in posttranslational modification of proteins to facilitate proper membrane anchoring and trafficking to lipid rafts, which is critical for many cell functions, including embryogenesis and neurogenesis. GPI biosynthesis is a multi-step process requiring the activity of over 25 distinct genes, most of them belonging to the phosphatidylinositol glycan (PIG) family and associated with rare neurodevelopmental disorders. PIGQ encodes the phosphatidylinositol glycan class Q protein and is part of the GPI-N-acetylglucosaminyltransferase complex that initiates GPI biosynthesis from phosphatidylinositol (PI) and N-acetylglucosamine (GlcNAc) on the cytoplasmic side of the endoplasmic reticulum (ER). Pathogenic variants in the PIGQ gene have been previously reported in 10 patients with congenital hypotonia, early-infantile epileptic encephalopathy, and premature death occurring in more than half cases. We detected a novel homozygous variant in PIGQ (NM_004204.5: c.1631dupA; p.Tyr544fs*79) by WES trio-analysis of a male patient with a neurodevelopmental disorder characterized by nonprogressive congenital ataxia, intellectual disability, generalized epilepsy, and cerebellar atrophy. Flow cytometry confirmed deficiency of several GPI-anchored proteins on leukocytes (CD14, FLAER). Clinical features of this case broaden the phenotypic spectrum of PIGQ-related GPI deficiency, outlining the importance of glycophosphatidylinositol (GPI) anchor pathway in the pathogenesis of cerebellar ataxia.

A clinical diagnostic algorithm for early onset cerebellar ataxia

Early onset cerebellar Ataxia (EOAc) comprises a large group of rare heterogeneous disorders. Determination of the underlying etiology can be difficult given the broad differential diagnosis and the complexity of the genotype-phenotype relationships. This may change the diagnostic work-up into a time-consuming, costly and not always rewarding task. In this overview, the Childhood Ataxia and Cerebellar Group of the European Pediatric Neurology Society (CACG-EPNS) presents a diagnostic algorithm for EOAc patients. In seven consecutive steps, the algorithm leads the clinician through the diagnostic process, including EOA identification, application of the Inventory of Non-Ataxic Signs (INAS), consideration of the family history, neuro-imaging, laboratory investigations, genetic testing by array CGH and Next Generation Sequencing (NGS). In children with EOAc, this algorithm is intended to contribute to the diagnostic process and to allow uniform data entry in EOAc databases.

Mutations in the IRBIT domain of ITPR1 are a frequent cause of autosomal dominant nonprogressive congenital ataxia

Congenital ataxias are nonprogressive neurological disorders characterized by neonatal hypotonia, developmental delay and ataxia, variably associated with intellectual disability and other neurological or extraneurological features. We performed trio-based whole-exome sequencing of 12 families with congenital cerebellar and/or vermis atrophy in parallel with targeted next-generation sequencing of known ataxia genes (CACNA1A, ITPR1, KCNC3, ATP2B3 and GRM1) in 12 additional patients with a similar phenotype. Novel pathological mutations of ITPR1 (inositol 1,4,5-trisphosphate receptor, type 1) were found in seven patients from four families (4/24, ∼16.8%) all localized in the IRBIT (inositol triphosphate receptor binding protein) domain which plays an essential role in the regulation of neuronal plasticity and development. Our study expands the mutational spectrum of ITPR1-related congenital ataxia and indicates that ITPR1 gene screening should be implemented in this subgroup of ataxias.

Systematic extended and saturation prostate biopsy: when and how

The increasing incidence of prostate cancer is manly due to the improvement of systematic transrectal ultrasound-guided prostate biopsy techniques. The objective of this review is to analyze the different approaches and the most common schemes used to perform prostate biopsy, the role of the anesthetic procedures, of the complementary imaging methods and the histological evaluation of the biopsy results. The actual indications to perform prostate biopsy have been also critically reviewed. We performed a review of the literature by searching Medline Database with the following key words: prostate cancer, diagnosis, trans-rectal ultrasound (TRUS), prostate biopsy, anaesthesia and prognosis. Prostate biopsy is always performed under transrectal ultrasound guidance with both transrectal and transperineal approach, with a minimal core number of 10. The extended protocols include lateral peripheral zone cores and cores from lesions found on palpation or imaging. Saturation biopsies should be performed only in case of repeat biopsies. The refinement of effective local anesthesia has allowed to increase the number of biopsies without important side effects. Complementary imaging methods might be adopted in order to reduce the number of unnecessary procedures .The histological issues related to the number and the location of cores are still matter of debate as important prognostic factors. According to international guidelines, the factors most involved in performing prostate biopsy still include suspicious digital rectal examination and PSA. Both the transrectal and the transperineal approach in prostatic biopsy are valid in term of detection rate and low incidence of side effects. The initial biopsy scheme in mainly extended, saturation biopsy has to be considered only in the repeat setting, with the eventual help of the complementary imaging methods. The histological issues has to be considered about patient's prognosis.

Mutations in the AP1S2 gene encoding the sigma 2 subunit of the adaptor protein 1 complex are associated with syndromic X-linked mental retardation with hydrocephalus and calcifications in basal ganglia

Fried syndrome, first described in 1972, is a rare X-linked mental retardation that has been mapped by linkage to Xp22. Clinical characteristics include mental retardation, mild facial dysmorphism, calcifications of basal ganglia and hydrocephalus. A large four-generation family in which the affected males have striking clinical features of Fried syndrome were investigated for linkage to X-chromosome markers; the results showed that the gene for this condition lies within the interval DXS7109-DXS7593 in Xp22.2. In total, 60 candidate genes located in this region, including AP1S2, which was recently shown to be involved in mental retardation, were screened for mutations. A mutation in the third intron of AP1S2 was found in all affected male subjects in this large French family. The mutation resulted in skipping of exon 3, predicting a protein with three novel amino-acids and with termination at codon 64. In addition, the first known large Scottish family affected by Fried syndrome was reinvestigated, and a new nonsense mutation, p.Gln66X, was found in exon 3. Using CT, both affected patients from the French family who were analysed had marked calcifications of the basal ganglia, as previously observed in the first Scottish family, suggesting that the presence of distinctive basal ganglia calcification is an essential parameter to recognise this syndromic disorder. It may be possible to use this feature to identify families with X-linked mental retardation that should be screened for mutations in AP1S2.

Bilateral Renal Mass Suggestive of Cancer

We present the case of a 44-year old man, presenting with acute left flank pain and gross haematuria, affected by bilateral renal mass and massive para-aortic and mediastinic lymphadenopathy, highly suspicious for metastatic renal cancer.

Oligophrenin 1 mutations frequently cause X-linked mental retardation with cerebellar hypoplasia

BACKGROUND

Mutations of oligophrenin 1, one of the first genes identified in nonspecific X-linked mental retardation (MRX), have been described in patients with moderate to severe cognitive impairment and predominant cerebellar hypoplasia, in the vermis.

OBJECTIVE

To further delineate the phenotypic and mutational spectrum of the syndrome, by screening oligophrenin 1 in two cohorts of male patients with mental retardation (MR) with or without known posterior fossa anomalies.

METHODS

Clinical examination, cognitive testing, MRI studies, and mutational analysis (denaturing gradient gel electrophoresis and direct sequencing) on blood lymphocytes were performed in 213 unrelated affected individuals: 196 patients classified as MRX and 17 patients with MR and previously detected cerebellar anomalies.

RESULTS

Four novel oligophrenin 1 mutations were identified. In the MRX group, two nonsense mutations were detected. In the MR group, two mutations were found: a deletion of exons 16 to 17 and a splice site mutation. All patients shared characteristic clinical, radiologic, and distinctive features with a degree of intrafamilial variability in motor and cognitive deficits.

CONCLUSIONS

Oligophrenin 1 mutations were found in 12% (2/17) of individuals with mental retardatin and known cerebellar anomalies and in 1% (2/196) of the X-linked mental retardation group.

The ageing male and erectile dysfunction

Erectile dysfunction is common in the ageing man and reliable therapies are needed. The pathophysiology of erectile dysfunction in this group mainly includes chronic ischaemia, which triggers the deterioration of cavernosal smooth muscle and the development of corporeal fibrosis. Assessing the ageing man with erectile dysfunction who seeks medical treatment should comprise a thorough medical and sexual history, a systemic and focused physical examination and selected blood tests. Oral drug therapy represents a safe and effective option for most ageing men.

X-linked congenital ataxia: a clinical and genetic study

We report on a family in which two males are affected with X-linked congenital ataxia (XCA). Clinical manifestations include severe hypotonia at birth, delay of early motor development, slow eye movements, and nonprogressive cerebellar ataxia. The neurological examination excluded a neuromuscular disease, mental retardation, and pyramidal tract involvement. Neuroimaging showed global cerebellar atrophy in both patients that was not evident in the first years of life. The clinical findings in this family are very similar to those in a Russian pedigree [Illarioskin et al., 1996: Ann Neurol 40:75-83] and outline a recognizable phenotype. Linkage studies in our family, using 28 highly polymorphic Généthon microsatellite markers evenly distributed along the X chromosome, excluded a 24 cM interval between DXS990 and DXS424 located within the previous candidate region of 54 cM, reducing the critical interval.

Clinical and molecular aspects of the Simpson-Golabi-Behmel syndrome

The Simpson-Golabi-Behmel syndrome (SGBS) is an overgrowth/multiple congenital anomalies/dysplasia syndrome caused by a mutant X-linked gene. The spectrum of its clinical manifestations is broad, varying from very mild forms in carrier females to infantile lethal forms in affected males. A typically affected male will show tall stature, "coarse" face, supernumerary nipples, congenital heart defect, and generalized muscular hypotonia. Mental development is normal in most cases. There is an increased risk of neoplasia in infancy, especially Wilms tumor. The SGBS gene spans 500 kilobases in the Xq26 region and contains eight exons. It encodes an extracellular proteoglycan, designated glypican 3 (GPC3), capable of interacting with the insulin-like growth factor IGF2. At present, only deletions of various sizes have been found in a number of affected families.

Cryoglobulinemia in HCVAb+ patients on chronic hemodialysis

OBJECTIVE

Striking evidence of HCV infection has been found in mixed cryoglobulinemia (MC) and HCV has been hypothesized to be the causative agent of this disease. To assess the association of C virus infection and cryoglobulinemia we studied cryoglobulin levels in 66 patients on maintenance hemodyalisis who were selected on the basis of HCVAb positivity and not because they were affected by liver disease. The control group was made up of 45 patients also on hemodyalisis but without HCV infection.

RESULTS

Circulating cryoglobulins were found in 34 (52%) of 66 HCV+ patients: the cryocrit was < 1% in 20, 1 to 5% in 12, and > 5% in 2 patients. The cryoglobulins were classified by immunofixation as type II in 8 and type III in 8 others; identification was not possible in 18 cases. In the HCVAb- control group untypable cryoglobulins were detected in 9% of the patients at < 1% by volume. No correlation was found between these data and the liver disease detected by biohumoral tests.

CONCLUSIONS

Our data confirm the close link between HCV infection and cryoglobulins; the prevalence of circulating cryoglobulins in uremic HCVAb+ patients is very close to that found in HCV-related liver disease.

HCV and monoclonal gammopathies

OBJECTIVE

To determine the prevalence of antibodies against HCV in monoclonal gammopathies with and without cryoglobulinemic activity.

METHODS

201 patients were divided into two groups: (I) 94 patients with monoclonal gammopathies with cryoglobulinemic activity, and (II) 107 with monoclonal gammopathies without cryoglobulinemic activity. Cryoglobulins were characterized by immunofixation; HCVAb were detected using second-generation ELISA and RIBA methods; in 38 cases the presence of HCV in peripheral blood mononuclear cells was evaluated by PCR.

RESULTS

The HCVAb prevalence, as evaluated by RIBA, in Group I was 69.1% while in Group II it was only 14.9%. Histological and immunohistochemical study of the bone marrow in Group I patients frequently showed signs of nodular B-cell clonal expansion.

CONCLUSIONS

Our data confirm the existence of a close correlation between HCV infection and the monoclonal gammopathies with cryoglobulinemic activity. HCV-positive cryoglobulinemic is characterized by self-limiting IgM monoclonal expansion associated with histological aspects of bone marrow lymphoid nodules that do not expand in the course of the disease like classic evolving lymphoproliferative processes.

A cytomorphological and immunohistochemical study of bone marrow in the diagnosis of essential mixed type II cryoglobulinemia

BACKGROUND

Type II essential cryoglobulinemia may be associated with a lymphoproliferative disorder of beta lineage that shows a low degree of malignancy.

METHODS AND RESULTS

The authors report a case recorded of 35 patients (30 females and 5 males) affected by mixed cryoglobulinemia type II (MC II) that has been typed by immunofixation, a procedure that allows the identification of minute amounts of monoclonal components. In 20 patients with the "essential" form, the bone marrow histology revealed the presence of nodular aggregates of lymphocytes that were consistent with the diagnosis of immunocytoma in 14 cases and of early stage plasmocytoma in 1 case. The immunohistochemical analysis carried out in 5 of these cases allowed the identification of B lymphocytes in the nodules, thus confirming the diagnosis of low malignancy lymphoma. In our series the percentage of proliferative disorders of B lymphocyte lineage was 66%.

CONCLUSIONS

Our results indicate that the cytohistological analysis of bone marrow is highly recommended in the study of essential mixed cryoglobulinemia and that histological analysis supplemented with immunohistochemistry is preferred to the simple cytological analysis of bone aspirate.

Systolic time intervals in patent ductus arteriosus before and after corrective surgery

Systolic time intervals (STI) were analyzed in 11 patients with isolated patent ductus arteriosus (PDA) and unidirectional left-to-right shunt, before, shortly after (within 2 months) and a long time (at least 10 years) after the corrective surgery. The measurements were obtained from simultaneous high speed photographic recordings of electrocardiogram, external carotid pulse and phonocardiogram. Before the operation, the left ventricular ejection time (LVET) was significantly prolonged (p less than 0.01) and this abnormality was correlated with Qp/Qs (r = 0.74, p less than 0.01). Shortly after the operation, the LVET was shorter than normal, and became normal only a long time after. It is concluded that the most likely explanation for these abnormalities is: 1) before the operation, the increased stroke volume of the left ventricle secondary to the shunt, and 2) after corrective surgery, the depressed contractility of the left ventricle secondary to the long-standing volume overload which tends to persist after the corrective surgery.

[Association of primary malignant neoplasms in the same patient]

The Authors have examined the problem concerning the presence of "Double malignancies" in the same patient, on the basis of a review of the literature and of an investigation of their own case material (nine patients: six with double solid tumours and three with a solid tumour and an associated haematologic neoplasia). The Authors discuss the time sequence of the two neoplastic processes and the immunological pattern (T and B lymphocytes) of all cases.

[Etiopathogenetical, clinical and therapeutic considerations on meningo-encephalic localizations in acute lymphatic leukemias: personal contribution]

The aetiology, pathogenesis, clinical forms and therapeutic attempts carried out in connection with the central nervous system localizations in acute lymphoblastic leukaemia, on the basis of an extensive review of the literature and of personal experience are examined. The particular role which central nervous system leukaemia plays on the subsequent clinical course of the disease is stressed and the efforts made, both prophylactically and therapeutically, in order to decrease the incidence of this complication, which invariably has a deteriorating influence of the progress of the disease are described.