Frequency and antimicrobial susceptibility of Shigella species isolated in Children Medical Center Hospital,Tehran, Iran, 2001-2006

Appropriate antimicrobial treatment of shigellosis depends on identifying its changing resistance pattern over time. We evaluated 15,255 stool culture submitted from July 2001 to June 2006 to the Laboratory of Children Medical Center Hospital. Specimen culture, bacterial identification, and disk diffusion susceptibility testing were performed according to National Committee for Clinical Laboratory Standards guidelines. From 15,255 stool samples, 682 (4.5%) were positive for Shigella species. The most common species of Shigella were S. flexneri (48%) and S. sonnei (45%); other results were S. dysenteriae (5%) and S. boydii (2%). The rate of Sensitivity to ceftriaxone (95%), ceftizoxime (94%), and nalidixic acid (84%) were among our isolates. Resistance to co-trimoxazole and ampicillin was 87% and 86%, respectively. S. flexneri was more multiresistant than other species (47.9%). Our isolates are overall most sensitive to ceftriaxone, ceftazidime, and nalidixic acid (> 84%). They were most resistant to co-trimoxazole and ampicillin (> 86%). Because resistance varies according to specific location, continuous local monitoring of resistance patterns is necessary for the appropriate selection of empirical antimicrobial therapy.     

Evaluation of interleukin-12 receptor β1 and interferon gamma receptor 1 deficiency in patients with disseminated BCG infection

Introduction

Disseminated BCG infections among other complications of Bacillus Calmette–Guérin (BCG) vaccine are rare and have occurred in children with immunodeficiency disorders such as mendelian susceptibility to mycobacterial disease (MSMD) which could be due to defects in some elements of IL-12/IFN-γ axis. MSMD-causing mutations have been identified in 10 genes during the last two decades. Among them, mutations in the IL12Rβ1 and IFNγR1 genes constitute about 80% of recorded cases of MSMD syndrome. The aim of this study was to investigate IL-12Rβ1 and IFN-γR1 deficiencies in patients with disseminated BCG infection.

Analysis of RAB27A Gene in Griscelli Syndrome type 2: Novel Mutations Including a Deletion Hotspot

INTRODUCTION: Griscelli syndrome type 2 is an autosomal recessive disorder characterized by pigmentary dilution and occurrence of acute phases of hemophagocytosis. The disease is caused by mutations in RAB27A gene, coding a small GTPase involved in terminal phases of cytotoxic granule/melanosome exocytosis. MATERIALS AND METHODS: We describe the result of mutation analysis among nine patients from seven non-related Persian families. We present four novel mutations including a deletion hot spot (514del 5). CONCLUSION: This hot spot is flanked by "direct repeats" of nucleotides, which are previously shown to be associated with areas of recurrent small deletions.     

Detection of Epstein-Barr virus DNA in plasma and lymph node biopsy samples of pediatric and adult patients with Hodgkin lymphoma

Hodgkin lymphoma (HL) is commonly associated with latent Epstein-Barr virus (EBV) infection. The aim of this study is a molecular analysis of the EBV status in both involved lymph node biopsies and plasma samples of patients with HL. Plasma and lymph node biopsy samples obtained from 15 pediatric and 10 adult HL patients were examined for EBV DNA using conventional polymerase chain reaction (PCR). The control group consisted of 30 healthy pediatrics and adults. In addition, immunoglobulin G (IgG) anti-EBV nuclear antigen (EBNA)-1 antibody was determined in sera of patients and controls using enzyme-linked immunosorbent assay (ELISA). IgG Anti EBNA-1 antibody was detected in 21 (84%) and 8 (26%) of patients and controls, respectively (P < .05). EBV DNA was detected in 12 (48%) and 1 (3%) plasma samples of patient and control cases, respectively. Significant difference was observed in plasma DNA detection between patients and controls (P < .05). Comparison of EBV DNA detection in plasma and biopsy samples between children and adult patients was only significant for plasma samples (P = .025). Significant correlation was observed in positive detection of EBV DNA between plasma and biopsy samples of the same individual (P < .001, r = .923). Frequency of EBV DNA in plasma and biopsy samples obtained from mixed-cellularity subgroup was higher than the nodular sclerosis; however, no significant difference was observed between these 2 subgroups. EBV detection in plasma of childhood Hodgkin lymphoma in a population with EBV seroconversion might be of value as a biomarker for EBV-associated Hodgkin lymphoma.     

High prevalence of latent tuberculosis in hematopoietic stem cell transplant recipients: A First Report

TB is an increasing health problem, and patients undergoing HSCT are more prone to develop tuberculosis. The aim of our study was to evaluate prevalence of latent tuberculosis in HSCT recipients. In this study, 84 patients (2 months to 18 years) who were candidates for HSCT at the referral hospital of Tehran Children's Medical Center were enrolled. The TST and the QFT‐GIT test were performed in all 84 patients, simultaneously. LTBI was considered when one of the tests was positive. Overall, the prevalence of LTBI in HSCT recipients in our study was 12% (10 cases). TST induration ≥5 mm was seen in only three patients (3.5%). Eight patients (9.5%) had a positive result for IGRA test, and 11 of them (13%) had indeterminate QFT‐GIT result. The agreement between the TST results (induration size ≥5 mm) and the QFT‐GIT results was poor (kappa = 0.14). In conclusion, there was a high rate of discordance between TST and IGRA results with many more positive QFT‐GIT tests. However, more studies are needed in this population to determine whether this discordance reflects true infection.     

Novel BTK mutation presenting with vaccine-associated paralytic poliomyelitis

Oral polio vaccine (OPV) has been used safely and efficiently for more than 40 years in preventive medicine. Vaccine-associated paralytic poliomyelitis (VAPP) is a rare adverse event of OPV due to reversion of the vaccine strain virus to a neurovirulent strain. VAPP can occur in healthy recipients or their close contacts. However, persons with primary humoral immunodeficiencies are at a much higher risk. X-linked agammaglobulinemia (XLA) is a prototypic humoral deficiency caused by mutations in the Bruton’s tyrosine kinase (BTK) gene. In addition to susceptibility to bacterial infections, patients with XLA are especially prone to enteroviruses. Here, we describe the occurrence of VAPP in a 15-month old Iranian boy. The child had received four doses of OPV, administered at birth, 2, 4, and 6 months of age. The patient’s infectious history was unremarkable. Laboratory evaluation revealed low levels of immunoglobulin G and CD19⁺ B cells of less than 1% of the lymphocyte population. A novel insertion (c.685_686insTTAC) in the SH3 domain of the BTK gene was detected as the underlying cause. Immunodeficient recipients of OPV can excrete poliovirus vaccine strains for a long period and are at risk of developing flaccid paralysis. They could also serve as a source of reverted virulent poliovirus to be reintroduced into the general population. This patient presented for the first time with VAPP, without any history of other major infections in 15 months. This suggests that a negative history for recurrent infections does not exclude the presence of a primary defect in the immune system.     

Management of Hospital Infection Control in Iran: A Need for Implementation of Multidisciplinary Approach

Nosocomial, or hospital-acquired, infections are considered the most common complications affecting hospitalized patients. According to results obtained from studies conducted in the Children Medical Center Hospital, a teaching children''s hospital and a tertiary care referral unit in Tehran, Iran, improvements in infection control practices in our hospital seem necessary. The aim of this study was to identify risk management and review potential hospital hazards that may pose a threat to the health as well as safety and welfare of patients in an Iranian referral hospital. Barriers to compliance and poor design of facilities, impractical guidelines and policies, lack of a framework for risk management, failure to apply behavioral-change theory, and insufficient obligation and enforcement by infection control personnel highlight the need of management systems in infection control in our hospital. In addition, surveillance and early reporting of infections, evaluation of risk-based interventions, and production of evidence-based guidelines in our country are recommended.