Avinoam Shiran MD, Eric Remer, Ihab Asmer, Basheer Karkabi MD, Eran Zittan MD, Aliza Cassel PhD, Mira Barak PhD, Orit Rozenberg PhD, Khaled Karkabi MD and Moshe Y. Flugelman MD
Abstract
Background: Hyperhomocysteinemia is associated with increased cardiovascular risk, but treatment with folic acid has no effect on outcome in unselected patient populations.
Objectives: To confirm previous observations on the association of homozygosity for the TT MTHFR genotype with B12 deficiency and endothelial dysfunction, and to investigate whether patients with B12 deficiency should be tested for 677MTHFR genotype.
Methods: We enrolled 100 individuals with B12 deficiency, tested them for the MTHFR C677T polymorphism and measured their homocysteine levels. Forearm endothelial function was checked in 23 B12-deficient individuals (13 with TT MTHFR genotype and 10 with CT or CC genotypes). Flow-mediated dilatation (FMD) was tested after short-term treatment with B12 and folic acid in 12 TT MTHFR homozygotes.
Results: Frequency of the TT MTHFR genotype was 28/100 (28%), compared with 47/313 (15%) in a previously published cohort of individuals with normal B12 levels (P = 0.005). Mean homocysteine level was 21.2 ± 16 mM among TT homozygotes as compared to 12.3 ± 5.6 mM in individuals with the CC or CT genotype (P = 0.008). FMD was abnormal (£ 6%) in 9/13 TT individuals with B12 deficiency (69%), and was still abnormal in 7/12 of those tested 6 weeks after B12 and folic treatment (58%).
Conclusions: Among individuals with B12 deficiency, the frequency of the TT MTHFR genotype was particularly high. The TT polymorphism was associated with endothelial dysfunction even after 6 weeks of treatment with B12 and folic acid. Based on our findings we suggest that B12 deficiency should be tested for MTHFR polymorphism to identify potential vascular abnormalities and increased cardiovascular risk.
Yael Shachor-Meyouhas MD, Alla Fesenko MD, Zipi Kra-Oz PhD, Irina Zaidman MD, Moran Szwarcwort-Cohen PhD, Einat Shafran MSc and Imad Kassis MD
Abstract
Background: Human herpes virus-6 (HHV-6) reactivation after hematopoietic stem cell transplantation (HSCT) is well known and has been linked with several clinical manifestations. The significance of HHV-6 viremia and related complications in this setting is still unclear.
Objective: To estimate the incidence of HHV-6 reactivation and associated morbidity in children undergoing allogeneic HSCT.
Methods: Blood samples obtained weekly (for cytomegalovirus surveillance) from children who underwent allogeneic HCST during the period January 2006–June 2010 were retrospectively tested for the presence of HHV-6 DNA using standard real-time polymerase chain reaction (PCR) assay. Clinical records were reviewed for correlation between viremia and clinical manifestations.
Results: Samples from 39 children were tested. Twenty patients had viral loads above 1000 copies/ml (51%) in at least one sample. Higher viral loads were seen in patients with primary immunodeficiency and in those with cord blood transplant. Attributable symptoms were present in 12 patients (60%) concurrently with positive PCR. Clinical manifestations spontaneously resolved without treatment in most cases, concomitantly with a decrease in viral load.
Conclusions: HHV6 reactivation during allogeneic HSCT is common. HHV-6 reactivation should be considered in patients with graft-vs-host disease-like rash, onset of CNS symptoms, delay in engraftment, and in patients after cord blood transplantation.
Naomi Nussinovitch MD PhD, Konstantin Esev MD, Merav Lidar MD, Udi Nussinovitch MD PhD and Avi Livneh MD
Abstract
Background: The relationship between autonomic nervous system (ANS) dysfunction and familial Mediterranean fever (FMF) is controversial. We recently reported normal heart rate variability (HRV), suggestive of normal ANS, in patients with uncomplicated FMF.
Objectives: To evaluate ANS function in colchicine non-responders by using the HRV tool.
Methods: The study group comprised 24 FMF patients suffering from recurrent FMF attacks despite treatment with a maximal colchicine dose. Electrocardiogram was measured under strict conditions and HRV parameters were calculated. Results were compared with age- and gender-matched unaffected controls.
Results: No statistically significant difference was found between the groups in any of the HRV parameters: maximal RR, minimal RR and average RR intervals, standard deviation of RR interval, square root of the mean squared differences of successive RR intervals, HRV triangular index, NN50, pNN50, and power spectral analysis parameters.
Conclusions: Although a small difference in HRV parameters in the current study cannot be entirely excluded, FMF patients in whom colchicine did not provide adequate symptomatic relief and who did not develop amyloidosis appear to have normal HRV parameters suggestive of normal ANS function, compared with healthy adults.
Barak Benjamin MD, Roy Zaltzman MD PhD, Baruch Shpitz MD, Carlos R. Gordon MD DSc and Shmuel Avital MD
Amnon Y. Zlotnick MD ,Tamar Gaspar MD, Ronen Rubinshtein MD, David Halon MD and Amir Elami MD