Levent Doganci

The evaluation of FASTPlaqueTBTM test for the rapid diagnosis of tuberculosis

FASTPlaqueTB (Biotec Laboratories Ltd., Ipswich, UK) is a rapid test which utilizes bacteriophage amplification technology for the detection of viable Mycobacterium tuberculosis in clinical specimens. We evaluated performance of the FASTPlaqueTB test by comparing with BACTEC 460 TB culture system (Becton Dickinson Co., Maryland, USA), polymerase chain reaction (PCR) and acid fast bacilli (AFB) smear methods. We investigated 192 sputum specimens collected from the patients suspected of having pulmonary TB by AFB smear, BACTEC 460 TB culture system, PCR and FASTPlaqueTB test. The sensitivity of AFB smear, PCR and FASTPlaqueTB test were 57.8%, 84.4% and 87.5% respectively when we accepted BACTEC 460 TB culture system as gold standard. We conclude that FASTPlaqueTB test has a good potential for rapid diagnosis of Mycobacterium tuberculosis as a result of the evaluation of these three tests by comparison to the BACTEC 460 TB culture system.

The evaluation of diagnostic methods for the detection of Helicobacter pylori in gastric biopsy specimens

PCR is a rapid, sensitive and accurate method for the specific detection of Helicobacter pylori from gastric biopsy specimens. In our study, 104 gastric tissue specimens from symptomatic adult patients were examined by staining, culture, PCR and nested PCR methods for detection of H. pylori. According to our results, positivity was achieved in 24% (25/104) with Giemsa staining, 34% (36/104) with histopathology, 36% (38/104) with PCR and 41% (43/104) with nested PCR respectively, whereas H. pylori was isolated in only 33% (35/104) of the cultures on the biopsy specimens. Both the sensitivity and the positive predictive value of the nested PCR method were 100%, and both the specificity and negative predictive value were 98%. As a conclusion, our results suggest the nested PCR as a highly valuable method in the detection of H. pylori with a reasonably high sensitivity and specificity.

Laboratory diagnosis of enteroviral infections of the central nervous system by using a nested RT-polymerase chain reaction (PCR) assay

Enteroviruses are the most common pathogens identified in infants hospitalized for suspected aseptic meningitis. Rapid detection of enterovirus infection is essential in taking the decision for treatment with antiviral agents and applying infection control measures in hospitalized pediatric patients. The purpose of this study was to compare the results of conventional virus isolation with those of enteroviral RNA detection by reverse transcription (RT)-PCR method in identical specimens from cases of suspected aseptic meningitis. Cerebrospinal fluid (CSF) samples were collected for viral examination from 68 pediatric patients with suspected aseptic meningitis from 1999 to 2002. These samples were inoculated in HeLa, Hep-2 and RD cell culture. The viral RNA was investigated by in-house RT-PCR method. The isolated viruses were typed by neutralization test. 36 of the 68 specimens were detected to be enterovirus positive by culture method, while 43 of them yielded positive results when RT-PCR method is used. Discrepancies occurred between the two methods in 15 specimens. While 11 specimens were positive by RT-PCR, these are found to be culture-negative. The isolated viruses were typed as Echovirus 30 (n: 30), Group B coxsackievirus (n: 5) and one isolate could not be typed by neutralization. Because of higher sensitivity and rapidity of RT-PCR, it is superior (p = 0.016) to virus culture of CSF for the diagnosis of enterovirus meningitis. Although the clinical usefulness of viral culture from CSF is limited, the final laboratory identification needs cultural techniques.

Prevalence of Cryptosporidium sp. in Patients with Neoplasia and Diarrhea

The prevalence of Cryptosporidium sp. was investigated in fecal specimens from 106 patients with neoplasia and diarrhea (74 females, 32 males) by using Ziehl-Neelsen and Giemsa stains. Oocystic forms of Cryptosporidium sp. were found in 18 (17%) of these patients. No oocystic form of Cryptosporidium sp. was detected in the control group of 60 patients with neoplasia (37 females, 23 males) but without diarrhea. The frequent findings of Cryptosporidium sp. in patients with neoplasia and diarrhea who are undergoing chemotherapy indicates that a search for this organism is justified.

Genotyping of Turkish environmental Cryptococcus neoformans var. neoformans isolates by pulsed field gel electrophoresis and mating type

A total of 26 environmental Cryptococcus neoformans var. neoformans strains isolated from 634 samples of pigeon droppings collected from 54 different provinces of Turkey in 1996 and 1997 were included in this study. The results of pulsed‐field gel electrophoresis (PFGE) showed that the 26 strains could be separated into 24 different PFGE patterns. In a mating‐type study, of 26 strains, 20 were MATα, four were MATa, one was MATa/α and one was non‐typable by STE20 specific primers. By the polymerase chain reaction typing, all the isolates were serotype A. The extensive heterogeneity among these isolates suggests that a single clonal population may not be present in Turkey. Additionally, the presence of an AMATa/DMATα hybrid may indicate the existence of strains that are AMATa mating type in Turkish environment.

Cryptococcus neoformans varieties from material under the canopies of eucalyptus trees and pigeon dropping samples from four major cities in Jordan

To our best knowledge, any study related to the ecological distribution of Cryptococcus neoformans in Jordan does not exist in the medical literature. In order to determine the environmental occurrence of both varieties of Cryptococcus neoformans in Jordan, pigeon droppings and material under the canopies of eucalyptus trees were collected from four major cities of this country. For the isolation of Cryptococcus neoformans variety gattii from environmental sources, 500 samples of the mixed soil debris, including tree materials, under the eucalyptus trees from cities of Amman, Irbid, Jerash, and Ajlun were collected. Also, 509 samples of pigeon droppings were collected from the same cities for the isolation of Cryptococcus neoformans variety neoformans. After inoculating the samples onto modified Staib agar medium in Petri dishes, a total of 336 melanoid yeast colonies were picked up during screening process. At the end of serial mycological studies, none of these isolates was identified as Cryptococcus neoformans, but all were Cryptococcus species other than C. neoformans. For determining the exact status, more extensive environmental studies need to be done in the future.

Neisseria meningitidis W135, Turkey

We describe the first case of Neisseria meningitidis W135 meningitis in Turkey. The strain was genotypically unrelated to the clone (W)ET-37, isolated from Hajj pilgrims in 2000.

Crimean Congo hemorrhagic fever and diffuse alveolar haemorrhage

Although the pathology of Crimean Congo haemorrhagic fever (CCHF) is mainly related to a haemorrhagic process with secondary cytokine storm, there have been no published reports of this fatal disease being a cause of diffuse alveolar haemorrhage (DAH). There are many aetiological factors emphasizing the direct role of endothelial injury on DAH. We present the case of a young adult Turkish man with diffuse bilateral alveolar haemorrhage without an episode of gross haemoptysis caused by the CCHF virus. Successful clinical results and a rapid clinical and radiological clearance were obtained within few days after starting daily oral ribavirin treatment. This fatal infection should be considered to exist in any patient presenting with DAH, and should rapidly be treated with ribavirin. Another very important factor which should always be borne in mind is the contagious character of the CCHF virus. It is one of the most dangerous microorganisms transmitted from person to person. Even the bronchoscopes contaminated with patient blood carry a high risk for nosocomial spread to medical staff and other patients.

Panniculitis as the initial manifestation of brucellosis: a case report.

Here, we describe a 38-year-old male with an abrupt manifestation acute panniculitis as unusual presentation of brucellosis. Brucellosis is a reemerging disease in Turkey, and the disease is primarily transmitted from farm animals to humans. Farmers and shepherds are the major risk groups for brucellosis in Anatolia. Brucellosis may involve almost all systems and organs, including the skin, and may mimic a wide range of illness and syndromes. Although the cutaneous manifestation of brucellosis is not disease specific, but it occurs in about 6%-13% of patients with brucellosis. Some of these lesions including rashes, papules, ulcers, abscess, erythema nodosum, ecchymosed skin rash, purpura, and vasculitis may be seen frequently in brucellosis, but panniculitis is rarely described. The case confirmed by positive blood culture had manifest skin lesion as an initial finding represented by lobular panniculitis with vasculitis.

Short-term quinolones for successful eradication of multiply resistant vibrio cholerae in adult patients

There has been an increasing multiple drug resistance problem in Vibrio cholerae biotype Eltor, the causative agent of 7th pandemic. The aim of this study was to show in vitro and in vivo susceptibility and effectiveness of quinolones in the treatment of endemic cholera cases. Excellent results were obtained in 53 bacteriologically confirmed cholera patients treated with short-term ofloxacin and ciprofloxacin. To our knowledge, there has been no previous report on this subject in the international medical literature. Our results show that quinolones can be an alternative drug for the treatment of multiply resistant V. cholerae infections.