Silvia Bronstein MSc, Mazal Karpati PhD and Leah Peleg PhD
Background: Gaucher disease is the most prevalent inherited disorder among Ashkenazi Jews (carrier frequency of about 6%) and six mutations account for about 96% of their mutant alleles. Two mutations, N370S and R496H, have been reported only in mildly affected or asymptomatic patients, Due to the rarity of R496H, it was recommended that it be excluded from screening programs.
Objectives: To verify the frequency and trace the origin of Gaucher mutations in screened individuals whose Ashkenazi ethnicity was confirmed by the birthplace of their grandparents.
Methods: We conducted a retrospective analysis of the screened results for the period 2006–2011. Mutations were identified by restriction analysis, Tag-ItTM detection system, Pronto® diagnostic kit and Nanogen technology (NanoChip® 400).
Results: The heterozygote frequency of eight mutations was estimated in a cohort of 16,910 alleles. Two mutations, N370S and R496H, were the most frequent in our population. However, while the occurrence of N370S carriers was similar to other reports (1:19.4), that of R496H carriers was considerably elevated (1:207). Examination of the screened individuals' ethnicity showed a significant difference in the distribution pattern of the country of origin between the carriers of these two mutations.
Conclusions: The origin pattern differences between the two groups of heterozygotes might reflect a separate geographic region of introduction for various mutations. As a result, secondary subgroups could be formed within the Ashkenazi population. This might clarify the dissimilarities in the occurrence of R496H mutation reported by various centers.
Alon Nevet MD PhD, Havatzelet Yarden-Bilavsky MD, Shai Ashkenazi MD MSc and Gilat Livni MD
Background: C-reactive protein (CRP) is often used to distinguish bacterial from viral infections. However, the CRP level does have implications, which depend on the clinical scenario and are still under research.
Objectives: To evaluate the distribution of CRP levels in children with primary herpetic gingivostomatitis.
Methods: The electronic database of a tertiary pediatric medical center was searched for all inpatients with a diagnosis of primary herpetic gingivostomatitis without bacterial co-infection. Background and clinical information was collected and CRP levels were analyzed.
Results: The study group consisted of 66 patients aged 8 months to 7.1 years who met the study criteria. The average CRP was 7.4 mg/dl (normal < 0.5 mg/dl). More than a third of the patients had a level higher than 7 mg/dl.
Conclusions: High values of CRP are prevalent in patients with primary herpetic gingivostomatitis, similar to adenoviral infections and some bacterial infections.
Michael Arad MD Msc, Lorenzo Monserrat MD PhD, Shiraz Haron-Khun MSc, Jonathan G. Seidman PhD, Christine E. Seidman MD, Eloisa Arbustini MD PhD, Michael Glikson MD and Dov Freimark MD
Background: Hypertrophic cardiomyopathy (HCM) is a familial disease with autosomal dominant inheritance and age-dependent penetrance, caused primarily by mutations of sarcomere genes. Because the clinical variability of HCM is related to its genetic heterogeneity, genetic studies may improve the diagnosis and prognostic evaluation in HCM.
Objectives: To analyze the impact of genetic diagnosis on the clinical management of HCM.
Methods: Genetic studies were performed for either research or clinical reasons. Once the disease-causing mutation was identified, the management plan was reevaluated. Family members were invited to receive genetic counseling and encouraged to be tested for the mutation.
Results: Ten mutations in sarcomere protein genes were identified in 9 probands: 2 novel and 8 previously described. Advanced heart failure or sudden death in a young person prompted the genetic study in 8 of the 9 families. Of 98 relatives available for genotyping, only 53 (54%) agreed to be tested. The compliance was higher in families with sudden death and lower in what appeared to be sporadic HCM or elderly-onset disease. Among the healthy we identified 9 carriers and 19 non-carriers. In 6 individuals the test result resolved an uncertainty about "possible HCM." In several cases the genetic result was also used for family planning and played a role in decisions on cardioverter-defibrillator implantation.
Conclusions: Recurrence of a same mutation in different families created an opportunity to apply the information from the literature for risk stratification of individual patients. We suggest that the clinical context determine the indication for genetic testing and interpretation of the results.
Ricardo Silvariño MD MSc, Oscar Noboa MD and Ricard Cervera MD PhD FRCP
Basement membranes form an anatomic barrier that contains connective tissue. They are composed of type IV collagen, laminin and proteoglycans. Anti-basement membrane antibodies bind to the non-collagen site of the α3 chain of type IV collagen. A group of renal diseases, pulmonary diseases and perhaps others affecting different organs have long been associated with the presence of antibodies directed against glomerular basement membrane (GBM), alveolar basement membrane and tubular basement membrane. Goodpasture disease has a frequency of 0.5 to 1 case by million/year, and is responsible for up to 20% of crescentic glomerulonephritis in renal biopsy. It has been associated with genetic and immune abnormalities and there are usually environmental triggers preceding clinical onset. Renal disease can occur isolated or in association with pulmonary hemorrhage. In general, renal disease has a rapid progression that determines severe compromise, with rare spontaneous resolution. The diagnosis of Goodpasture disease requires the presence of the anti-GBM antibody, either in circulation or in renal tissue. The prognosis of non-treated patients is poor. The standard of care is plasma exchange combined with prednisone and cyclophosphamide. Anti-GBM antibody levels must be monitored frequently until their disappearance, and then every 6 months to confirm sustained remission in the absence of clinical signs of recurrence. Prognosis of the disease is strongly associated with its initial presentation. Survival rates are related to the degree of renal compromise at onset of the disease. Recurrence of the disease post-transplantation is low.