Mogahid M Elhassan

Prevalence of Nocardia species among HIV-positive patients with suspected tuberculosis:

The objective of the study was to determine the frequency of nocardiosis in HIV-positive and HIV-negative individuals clinically suspected of having tuberculosis (TB). The study population (n = 171) were those who attended chest hospitals in Khartoum State, Sudan, between January and March 2010. The patients suffered from pulmonary infections with positive acid-fast bacilli. Blood (n = 171) and sputum (n = 171) samples were collected simultaneously. Blood samples were tested serologically for the presence of antibodies using HIV/Intensified Combination Prevention (ICP) test and sputum were cultured onto Lowenstein Jensen slants according to standard methods. Isolates showing rapid growth characteristic of Nocardiae were subcultured and subsequently identified using glucose yeast extract agar medium. All candidates in the study population (n = 171) suffered from pulmonary infections, nocardiosis was diagnosed in 4% (n = 7), HIV-positive cases were 17 (9.9%). Five Nocardia species were isolated from HIV-negative patients whereas two were from HIV-positive patients. Nocardia spp. cause pulmonary infections (4.09%) in both immunocompetent (2.92%) as well as immunocompromised (1.17%) patients who attend chest clinics in Sudan.

Absence of the mecA Gene in Methicillin Resistant Staphylococcus aureus Isolated from Different Clinical Specimens in Shendi City, Sudan.

Absolute dependence on mecA gene as the defining standard in determining the resistance of S. aureus to methicillin became the subject of distrust by many researchers. The present study aimed to determine the frequency of mecA gene in methicillin resistant S. aureus (MRSA) isolates using polymerase chain reaction and to correlate its presence to conventional method. In this regard, two hundred S. aureus isolates were collected from patients with different diseases attending different hospitals in Shandi City, Sudan. Phenotypic Kirby-Bauer method confirmed the existence of methicillin resistant S. aureus in 61.5% of the subjected isolates with MICs ranging from 4 μg/mL to 256 μg/mL when using E-test. However, when amplifying a 310 bp fragment of the mecA gene by PCR, twelve out of the 123 MRSA isolates (9.8%) were mecA negative, whereas all the 77 methicillin sensitive S. aureus (MSSA) were mecA negative. In conclusion, this study drew attention to the credibility of the mecA gene and its usefulness in the detection of all MRSA strains without referring to the traditional methods. Hence, it is highly recommended to consider alternative mechanisms for β-lactam resistance that may compete with mecA gene in the emergence of MRSA phenomenon in the community.

Challenges in diagnosing tuberculosis in children: a comparative study from Sudan

OBJECTIVES The diagnosis of tuberculosis (TB) in children is challenging due to insufficient specimen material and the scarcity of bacilli in specimens. This study aimed to evaluate methods for diagnosing TB in children in Sudan. METHODS Patients (N=197) were subjected to the tuberculin skin test (TST). Gastric lavage or sputum specimens were then collected, processed, and cultured as per standard procedures. RESULTS Culture on Löwenstein-Jensen medium, the reference standard, revealed growth in 16.2% of the specimens. Comparative analysis showed that 43.7% were positive for the TST (sensitivity 100%, specificity 67.3%), 8.1% were positive by Ziehl-Neelsen stain (sensitivity 43.8%, specificity 98.8%), 11.2% by auramine stain (sensitivity 56.3%, specificity 98.8%), and 17.8% were positive for PCR amplification of the IS6110 sequence (sensitivity 100%, specificity 98.8%). CONCLUSIONS It is concluded that whilst TST and IS6110 achieved 100% sensitivity based on the reference standard of culture, the latter was more specific. The TST is recommended for routine diagnosis and the use of PCR for particular cases, depending on the facilities and the urgency.

Multi-drug resistance tuberculosis (MDR-TB) in Kassala State, Eastern Sudan

This study investigates the prevalence of drug resistance and mutations in rpoB gene among Mycobacterium tuberculosis isolates from Kassala State, Sudan. In a cross-sectional study during 2011, sputum specimens (n = 90) were examined microscopically and grown cultures were identified by analysing IS6110 insertion sequence. Antimicrobial sensitivity and mutations in the rpoB gene were determined. Of the 90 specimens found which were positive for acid-fast bacilli (AFB), 65 (72.2%) showed growth of mycobacteria. Sixty (66.7%) of these were M. tuberculosis, 5 (5.6%) were rapidly growing mycobacteria and 10 (11.1%) revealed no growth. Of the 60 M. tuberculosis, 31 (51.7%) were drug resistant, including 18 multidrug resistant TB (30%), and 15 (83.3%) demonstrated mutations in the rpoB gene. Isoniazid and rifampicin revealed the highest resistance rates (64.5%, 61.3%, respectively). In conclusion, drug resistance M. tuberculosis in Kassala State was high (30%) and was found to be mainly (83.3%) due to mutations in the rpoB gene.

Burden of Multidrug Resistant Mycobacterium tuberculosis Among New Cases in Al-Madinah Al-Monawarah, Saudi Arabia

Background: The pattern of Mycobacterium tuberculosis susceptibility to first line drugs and multidrug resistance in Al-Madinah Al-Munawarah, a seasonally overcrowded are during Hajj and Omrah, is not well studied. Objective: This study aimed to investigate anti-tuberculosis drug resistance and its distribution among new cases in Al-Madinah Al-Monawarah. Methods: Study subjects included 622 patients with first time confirmed TB referred to the central tuberculosis laboratory in Al-Madinah between January 2012 and December 2014. Results: Out of the 622 isolates, 99 (15.9%) were Mycobacteria Other Than Tuberculosis (MOTTS) and 25 (4.0%), three of which (12%) were children under five years of age, revealed multidrug resistance (MDR). Monoresistance to isoniazid (H) was (1.8%), to rifampin (R) was (1.4%), to streptomycin (S) was (1.9%) to ethambutol (E) was (1.1%) and to pyrazinamide (Z) was (2.1%). Conclusion: Being among the new cases, multidrug resistant tuberculosis (MDR TB) is supposed to be caused by strains which are originally multidrug resistant. Neither nationality nor gender was found to be associated with MDR TB. Since 12% of MDR cases were among children, a probability of primary infection with MDR strains is to be considered. Moreover, mass gathering during Hajj and Omrah seasons does not seem to increase the burden of MDR in the region. However, further investigation is needed to molecularly characterize MDR isolates and their phylogenetics and geographical origin.

Elevated TGF-beta levels in drug-resistant visceral leishmaniasis.

BACKGROUND Poor and neglected populations in Africa are particularly affected with visceral leishmaniasis. The widespread emergence of resistance to pentavalent antimonials occurs globally and the unavailability of a vaccine in clinical use constitutes a major obstacle in disease control. OBJECTIVE To investigate the cytokine profile in human visceral leishmaniasis. DESIGN A cross-sectional laboratory-based study. SETTING Single center study carried out at the Institute of Endemic Diseases, University of Khartoum, Sudan. PATIENTS AND METHODS Soluble lysates of L major and L donovani were used to stimulate the lymphocytes of two groups of confirmed VL patients (group 1 [n=20] had respond to pentostam treatment and group 2 [n=5] were recorded as drug resistant after follow up) in a cellular proliferation assay and the levels of IFNγ, IL-10, TNFα and TGFβ were detected by cytokine ELISA. MAIN OUTCOME MEASURES Levels of IFNγ, TNFα, IL-10 and TGFβ. RESULTS A significant increase of IFNγ and TNFα levels were reported in stimulated cells of drug susceptible and drug resistant groups, but no significant difference in IL-10 production was observed between the different antigens or between the patients groups. TGFβ from stimulated lymphocytes was secreted in statistically significant amounts in patients reported as drug resistant in response to both L major and L donovani antigens (P<.001). CONCLUSIONS In VL patients, IFNγ and TNFα are extremely produced in response to in vitro re-stimulation which means that the parasitic infection, although virulent and chronic, does not render patients as immunocompromised. However, TGFβ is mostly associated with treatment failure. LIMITATIONS This study assessed secretory TGFβ. A study with a larger sample size to assess TGFβ gene expression and to follow its intracytoplasmic synthesis in drug resistant VL patients is recommended.

Epidemiological trends of cutaneous Leishmaniasis in Al‑Madinah Al‑Munawarah province, western region of Saudi Arabia

Objective: To investigate the epidemiological trends of cutaneous leishmaniasis (CL) in Al-Madinah Al-Munawarah, western region of KSA. Materials and Methods: Four hundred and sixty-seven parasitologically confirmed CL cases attending Al-Meeqat Hospital, Al-Madinah, during 2012–2015, were included in this study. Results: Both Saudi and non-Saudi nationals were infected, with the highest infection rate being among Saudis (68.7%). Males were more affected than females as 86.9% of the total CL cases were males. Moreover, CL was prevalent in all age groups with higher frequency among young adults and adolescents (23.1% and 22.7%, respectively). Interestingly, almost all the patients in the adolescent and child age groups were Saudis (96.2% and 93.5%, respectively). Considering geographical distribution, the highest percentage of the cases (40.5%) were from the northern parts of Al-Madinah province while the eastern parts reported the least infection rate (7.3%). Few cases (2.5%) were supposed to encounter the infection abroad. Additionally, the frequency of infection was found to follow a seasonal distribution. Regarding treatment, pentostam, ketoconazole, or cryotherapy were the treatment options usually used. Conclusion: CL is prevalent in Al-Madinah Al-Munawarah area and new foci are being introduced. Thus, detailed studies with large surveillances regarding vector and reservoir hosts in and around the area are needed.

Isolation and molecular identification of actinomycetes from mycetoma patients in Sudan

Introduction: In order to minimize chance of amputation due to actinomycetoma, it is important to correctly identify the causative agents. Microscopic examination of grains is not definite and further confirmatory diagnostic tests are needed. This study aims to investigate the prevalence of actinomycetoma and to explore the usefulness of strb1 gene in the diagnosis of the disease. Materials & Methods: The present study is a prospective cross-section laboratory-based study in which clinical samples (n = 100) from patients with mycetoma lesions were collected. The samples were cultured on Lowenstein Jensen and glucose yeast extract agar media. Grown colonies were initially identified using Grams stain, Ziehl Neelsen stain, and selected biochemical reactions. Confirmation was done by the analysis of polymerase chain reaction amplified strb1 gene. Results: Actinomycetoma was represented by a high ratio (12%) among the study population. Nine out of the 12 isolates (75%) were found to belong to the genus Streptomyces; whereas three isolates (25%) were identified as Nocardia spp. on the basis of phenotypic and mycolic acid contents. Conclusion: It could be concluded that actinomycetoma exists with significant prevalence (12%) among patients investigated in the present study. Streptomyces is the most important etiological agent of actinomycetoma compared to Nocardia.