Archives of Clinical Infectious Diseases
Volume:6 Issue: 2, Apr 2011

Advancements in molecular technology increased our understanding of genetic mechanism of drug resistance. Nowadays, the chance of rapid detection of resistant Mycobacterium tuberculosis (M. tuberculosis) strains is increased. In the present study, we aimed to investigate the sensitivity and specificity of PCR-SSCP for detecting susceptible and resistant strains of M. tuberculosis compared with DNA sequencing.Patients and To calculate the sensitivity and specificity of PCR-SSCP assay to detect drug resistance in M. tuberculosis, respiratory samples were collected from suspected patients referred to Mycobacteriology Research Center (Masieh Daneshvary Hosptial) since 2002. Susceptibility testing against first line drugs was performed on 74 culture-positive specimens. Consequently, PCR-SSCP and DNA sequencing were performed on katG, inhA, ahpC and rpoB genes. Drug-susceptibility testing by the proportional method in selected samples revealed 16 MDR (21.6%), 23 mono-drug resistant (31%) and 35 susceptible strains (47.3%). In comparison with DNA sequencing as a gold standard for molecular methods, the sensitivity of PCR-SSCP assay for detecting of mutation in 315 codon of katG gene was 94.74% (CI=73.97%-99.87%) with 100% (CI=93.51%-100%) specificity. In contrast, the sensitivity and specificity of this assay in detecting of rpoB gene were 70.8% (CI=48.91%-87.38%) and 88% (CI=75.69%-95.47%), respectively. PCR-SSCP in combination with DNA sequencing can be used as screening method to detect MDR-TB and mono-drug resistant cases.

Diabetic foot infection is a debilitating disease that requires prompt diagnosis and treatment. In this study, we assessed inflammatory markers; serum Procalcitonin (PCT), c-reactive protein (CRP), erythrocyte sedimentation rate (ESR) and leukocyte counts in two groups of patients with infected and non-infected diabetic foot ulcer.Patients and A descriptive cross-sectional study was carried out on diabetic patients during 18 months in Firoozgar Hospital. Patients were divided in two groups according to Infectious Disease Society of America (IDSA) guideline for diagnosis and treatment of diabetic foot infections. Blood samples were drawn from venous lines for measurement of complete blood count (CBC), ESR, CRP, and PCT. Diagnostic values of serum PCT Levels were determined by immunoluminometric assay. SPSS version 15.0 software was used for analysis. Sixty adult patients were considered for this study. Thirty patients with infected ulcer with mean age of 57.5× 2.09 years and 30 with non- infected ulcers with mean age of 61.1± 1.9 years were evaluated.Patients with infected ulcers had significantly elevated levels of CRP, ESR and leukocyte counts in comparison with the non- infected ulcers. Serum PCT levels did not differ between the two groups. Our study suggests CRP, ESR and Leukocyte counts can be used to diagnose of infected ulcers. The role of PCT in localized infections should be determined in further studies.

Chlamydia trachomatis (C.trachomatis) is one of the most common curable STDs. Little information is available on its incidence among prisoner men. This study aimed to investigate the frequency of urogenital infection with C.trachomatis among imprisoned men as a high risk group.Patients and In this cross-sectional study, 130 imprisoned men aged 16-49 years in one of Tehran prisons were randomly selected. After completing informed consent, each volunteer dedicated a urine sampler and a completed questionnaire. DNA extraction and PCR assay were performed in Avicenna Research Institute. Among the 130 prisoner men, only 3 (2.3%) had positive PCR test results.Mean age of participants was 28.00 ±4.58 and the mean age at first sexual contact was 20.33 ±3.51. All had at least elementary education while 66.7% were unmarried and 33.3% were unemployed and had less than 1000000 Rails per month. Moreover, 33.3% were homeless and others living in rental houses. Furthermore, 66.6% had more than 4 sexual partners. There was no difference in condom use and none of them mentioned urinary discharge or dysuria. Additionally, 66.6% were IVDU and had more than 3 prison admissions. There was no report of HIV, HCV or HBV infection among them. The low incidence of C.trachomatis in this study showed that screening of asymptomatic men by PCR is not cost-effective and in order to obtain more epidemiological information, low-cost techniques such as serological methods can be recommended. Moreover, studies with broader distribution and higher sample size should be performed to determine real prevalence of chlamydia infection and make a definite decision about screening.

The plant materials play a major role in primary health care as therapeutic regimen in many developing countries. In the present study, the ethanol extracts of mentha spicata or spearmint (M. spicata) and mentha piperita or peppermint (M. piperita) have been used to inactive mycobacterium bovis (M. bovis) in comparison to isoniazid.Patients and After collecting and identifying the herbs, their ethanolic extract was prepared using percolation method. The extracts of M. spicata and M. piperita with different dilutions; 0.39,0.78,1.56,3.12,6.25,12.5,25,50,100,200,400 mg/ml were provided. M. bovis strain 1173 P2 was used in this study. This microorganism was confirmed by acid-fast staining (Ziehl-Neelsen). The bacteria were incubated at 37 °C for a long time by inoculation into Middle Brook broth (Difco). Biochemical tests such as niacin, nitrate and urease were performed to confirm the organism (e.g. Feingold)(1) Agar diffusion and MIC methods (McFarland standard method and diffusion disk) were used to determine the antimicrobial activity of ethanolic extracts and the inhibition zones formed on the media were measured with a transparent ruler in millimeters. The in vitro antibacterial activities of ethanolic extracts showed 0.39 mg/ ml consistency of M. spicata and 100 mg/ml consistency of M. piperita as the least concentrations which inhibit growth of M. bovis in comparison with isoniazid. According to our findings, extracts of M. spicata and M. piperita could be used as raw materials for phytotherapy because of their antibacterial activities against M. bovis as TB etiology.

This study was conducted to assess the prevalence of Hepatitis C virus (HCV), Hepatitis B virus (HBV) and Human immunodeficiency virus (HIV) among hemophilia and thalassemia patients.Patients and Present study was conducted from October 2008 to December 2010 in Isfahan, Iran. One thousand one hundred and sixty adult multi-transfused patients (822 males, 338 females, mean age 22.7±11.5 years) suffering from beta-thalassemia (n = 545) and hemophilia (n=615) were enrolled in the study. Blood samples were obtained from the patients and were tested for HBs Ag, Anti-HCV Ag and Anti- HIV Ab. HCV positive patients underwent genotype determination. Of 545 thalassemia patients, 312(57.2%) were male and 233 (42.8%) were female. From 615 hemophilia patients, 511(83%) were male and 104 (17%) were female. Chronic hepatitis was detected in 505(82.1%) hemophilia patients of which 495 (98%) were HCV Ab positive and 10 (2%) had HBsAg positive. The prevalence of HCV Ab positive and HBsAg positive in 56 (11%) thalassemia patients with chronic hepatitis was 50 (89.2%) and 6 (10.8%) respectively. None of the thalassemia and hemophilia patients were positive for HIV Ab. History of hepatitis in family is the major risk factors and HCV genotype 1 was the major genotype in our patients. HCV is the major virus of concern in multi-transfused patients. The strategies for prevention of HCV, HBV and HIV and safety of blood products in this respect have indeed been successful.

Helicobacter pylori (H. pylori) has several virulence factors such as vacA and cagA genes. Mosaicism in vacA alleles with two distinct families of vacA signal sequences (s1, s2) and two distinct families of middle region alleles (m1, m2) is reported. The aim of this study was determination of H. pylori vacA allelic types in Chaharmahal and Bakhtiyari province, Iran and their correlation with six different gastroduodenal diseases.Patients and This cross-sectional descriptive study was performed on 200 antral gastric biopsy specimens that were obtained from patients undergoing upper gastrointestinal tract endoscopy in Hajar Hospital of Shahrekord. Initially, H. pylori strains were identified by rapid urease test (RUT) and ureC primers, and thereafter, we used seven specific primers for detection of vacA genotypes. Statistical analyses were used to find their relationship to gastric disorders. The frequency of the vacA alleles, s1a/m1a, s1a/m1b, s1a/m2, s1b/m1a, s1b/m1b, s1b/m2, s1c/m1a, s1c/m1b, s1c/m2, s2/m1a, s2/m1b and s2/m2 were respectively, 27(16.46%), 8(4.87%), 45(28.43%), 7(4.26%), 5(3.04%), 10(6.09%), 12(7.31%), 4(2.43%), 18(10.97%), 6(3.65%), 0 and 22(13.41%). s1a/m2 strains were the most prevalent strains in this region and there was a considerable relationship between s1a/m1a, s1a/m2, s2/m2 and s1c/m1a with some gastric disorders. As the findings are different from other regions of the world, extended molecular epidemiologic investigations are recommended in other cities of Iran.

Animal bite is an important public health problem. In Iran, surveillance system carries out primary prevention for total animal bite cases in order to prevention of rabies. This study is carried out to investigate animal bite epidemiology in Birjand from 2002 to 2009.Patients and Standardized investigation form is used to record data from Birjand health center regarding demographic data of individuals, exposure status, treatment and biting animals between 2002 and 2009. The mostly affected individuals were in age group of 20-29 (23.9%), males (78.3%) and in rural residents (64.2%). Moreover, 86.3% were bitten by domestic animals and most cases were bitten by dog (80.3 %). Incidence rate of animal bites in Birjand was increased from 54.36 to 86.74 in 100 000 from 2002 to 2009. This study indicated that rabies surveillance in Birjand should focus on education to individuals, domestic animal vaccination and eradication of stray dogs.

Meningitis is a severe and potentially fatal form of tuberculosis. The diagnostic workup involves detection of acid-fast bacilli (AFB) in the cerebrospinal fluid (CSF) by microscopy or culture. However, the difficulty in detecting the organism poses a challenge in diagnosis. Cryptococcosis is an opportunistic fungal infection caused by cryptococcus neoformans. We presented central nervous system co-infection of tuberculosis and Cryptococcus neoformans which is extremely rare.Patient: The patient was a 35 year-old woman who was admitted in hospital due to fever, headache and changes of mental status. Physical examination revealed neck stiffness and positive Kernig's and Brudsinsky's signs. Cerebrospinal fluid analysis showed lymphocytic pleocytosis and culture of cerebrospinal fluid revealed mycobacterium tuberculosis and cryptococcus neoformans. Tuberculosis meningitis should be considered in patients with chronic meningitis especially in endemic areas. Cryptococcus neoformans meningitis may occur in immunocompromised and immuncompetent patients. Central nervous system co-infection with tuberculosis and Cryptococcus neoformans is possible.

Over several decades, morphological variation of Mycobacterium tuberculosis (M. tuberculosis) has engaged the attention of numerous investigators. The single point on which all investigators have agreed is that tubercle bacillus does not always manifest itself in the classical rod shape. While most commonly the organism appears as a granular rod, the other forms i.e., coccid, filament and club shapes are also present. Aside from the more purely academic aspect of the subject, the possible significance of variant forms in the etiology, prognosis, and control of tuberculosis infection were objects of heated controversies, even before 1900. These differences have never been resolved, and have been ignored by most recent workers. The main questions were centered on the following points: (1) Dose the tubercle bacillus produce endospore? (2) Does it normally undergo a complicated life cycle? (3) What is the importance of the non-acid-fast forms? (4) And what happens to the bacteria during latent infection? Today, based on various in-vitro and in-vivo models, the researchers agreed to consider M. tuberculosis as a two-phase microorganism which can appear either in its metabolically active acid-fast or in its inactive forms. It is the purpose of this chapter to review and discuss morphological variation and its challenges in M. tuberculosis. Furthermore, the cell shape and cell division were illustrated using atomic force microscopy. The present information will discuss the adaptation mechanism in M. tuberculosis and may help scientists to identify targets for novel therapies.