Abdelmageed M. Kambal

Evaluation of a brucelle enzyme immunoassay test (ELISA) in comparison with bacteriological culture and agglutination

An ELISA test for IgG and IgM antibrucella antibodies was found to be effective in diagnosis of human brucellosis. Assays for IgG and IgM in 30 culture-positive cases gave significant ELISA values. By the standard agglutination test, 10% of these cases gave readings less than 1:160. These are considered insignificant, taking 1:160 as the accepted cut-off value. Moreover, in an extra 135 samples from suspected brucella cases, where only serology was requested (77.6% of all cases), 7.4% were found to have IgM brucella antibodies by ELISA. In all of these, the corresponding agglutination titres were less than 1:80 and hence reported as insignificant. We report the detection of IgG and IgM antibodies in samples from patients with both acute and chronic disease. In few patients with acute disease, only IgM was detected. These findings are discussed in comparison with earlier studies. Finally, the ELISA test, in addition to measuring antibody classes directly, also detects incomplete antibodies. By this, it can efficiently replace the 2 mercaptoethanol test (2ME) and the Coombs antihuman-globulin test. This saves considerable laboratory cost and time.

Treatment of Disseminated Mycobacterial Infection with High-Dose IFN-γ in a Patient with IL-12Rβ1 Deficiency

IFN-γ has been used in the treatment of IL-12Rβ1 deficiency patients with disseminated BCG infection (BCGosis), but the optimal dose to reach efficacy is not clear. We used IFN-γ in the treatment of a 2.7-year-old patient with IL-12Rβ1 deficiency and refractory BCG-osis. IFNγ was started at a dose of 50 μg/m2 3 times per week. The dose was upgraded to 100 mcg/m2 after 3 months, then to 200 mcg/m2 6 months afterwards. Serum mycobactericidal activity and lymphocytes number and function were evaluated throughout the study. There was no clinical response to IFN-γ with 50 or 100 μg/m2 doses. However, there was some response to the 200 μg/m2 dose with no additional adverse effects. The serum mycobactericidal activity was not significantly different during the whole treatment period. Lymphocytes proliferation in response to PHA was significantly higher after 3 months of using the highest dose as compared to the lowest dose. The tuberculin skin test reaction remained persistently negative. We conclude that in a patient with IL-12Rβ1 deficiency, IFN-γ at a dose of 200 μg/m2, but not at lower dosages, was found to have a noticeable clinical effect with no additional adverse effects.

Isolation of Streptococcus milleri from clinical specimens

During a period of 26 months, 80 strains of Streptococcus milleri were isolated from 80 patients with clinical evidence of infection. More than a third of the isolates were from lesions related to the gastro-intestinal tract and a quarter from abscesses of various other sites. The haemolytic activity and group antigenic profile of these isolates are discussed. In addition, the clinical significance of S. milleri isolated from various sites is evaluated.

National surveillance of antimicrobial resistance among Gram-positive bacteria in Saudi Arabia

Abstract Background: Antimicrobial-resistant Gram-positive bacteria are important causes of serious infections. Methods: Between January and December 2009, we examined clinical Gram-positive isolates from 24 hospitals across Saudi Arabia. Results: Among the 13750 isolates, Staphylococcus aureus (62·3%) was the commonest, followed by non-group A beta-haemolytic streptococci (14·8%), group A beta-haemolytic streptococci (7·1%), coagulase-negative staphylococci (6·6%), pneumococci (6·0%), and enterococci (3·1%). Resistance rates were high among S. aureus (methicillin-resistant S. aureus: 32%), coagulase-negative staphylococci (oxacillin: 63%) and pneumococci (penicillin G: 33%; erythromycin: 26%; ceftriaxone: 11%); low among enterococci (vancomycin: 1%) and among beta-haemolytic streptococci. Resistance rates varied between regions, but comparison was complicated by differences in antibiotics tested. Many relevant antibiotics were tested against few isolates (e.g. ampicillin, vancomycin, and high-level gentamicin versus enterococci) while unhelpful tests were widely performed (e.g. cefotaxime, ceftriaxone, and imipenem versus staphylococci. Conclusion: Resistance is widespread in staphylococci and pneumococci, but not enterococci and beta-haemolytic streptococci in Saudi Arabia. Rationalization of antibiotic panels tested is urgently needed.

The Relative Importance of Shigella in the Aetiology of Childhood Gastroenteritis in Saudi Arabia

The role of shigella infection in childhood gastroenteritis was studied over a 2-year period. Shigella species were found in the faecal specimens of 70 (1%) of 7369 children with gastroenteritis, but in only 1 (0.1%) of 1130 controls. S. flexneri was the commonest isolate (51%), followed by S. sonnei (37%). Most shigella species were isolated during the winter. The prevalence of shigellosis was highest for children 1-5 years of age but equal for both sexes. Fever, abdominal cramps, vomiting, and bloody diarrhoea were the predominant clinical features. Of the shigella isolates, 73% were resistant to cotrimoxazole, 43% to ampicillin, and 41% to chloramphenicol. One-third of isolates were resistant to greater than or equal to 3 antibiotics. All isolates were susceptible to nalidixic acid. The illness was mild and self-limiting and most patients recovered without antimicrobial therapy.

Nosocomial transmission of community-acquired methicillin-resistant Staphylococcus aureus in a well-infant nursery of a teaching hospital

Background:  Infection due to community‐acquired strains of methicillin‐resistant Staphylococcus aureus (CA‐MRSA) has been reported with increasing frequency. Herein is described the nosocomial transmission of CA‐MRSA involving 13 neonates and two mothers in a well‐infant nursery in a teaching hospital in Saudi Arabia.

Childhood pneumococcal bacteraemia in Riyadh, Saudi Arabia

Forty-nine children with pneumococcal bacteraemia seen during a 5-year period (1 January 1991 to 31 December 1995) at King Khalid University Hospital were studied. The majority (61.2%) were under 2 years of age. The focus of infection was pneumonia, pharyngitis or undetermined in 28.6%, 18.4% and 20.4%, respectively. Diseases that had probably predisposed them to pneumococcal bacteraemia (mainly nephrotic syndrome) were encountered in 24.5% of cases. Forty-five per cent of the cases occurred during the summer season and in 29% the disease was nosocomially acquired. No death was recorded in this series and the reasons for this are discussed. Detection of pneumococcal antigens from blood taken for culture was successful in 96% of cases; this test is important in the diagnosis of pneumococcal bacteraemia in partially treated patients. Antimicrobial susceptibility testing showed 20.4% of the isolates to be relatively penicillin-resistant. Resistance to other antimicrobial agents was also recorded and multiple resistance was noted in 22% of isolates. There was a significant difference between the ceftriaxone MIC of the relatively penicillin-resistant strains compared with penicillin-sensitive strains. The emergence and the steady increase in the numbers of relatively penicillin-resistant pneumococcal strains in Saudi Arabia during the last 10 years are discussed.

Surgical Site Infection in a Teaching Hospital: A Prospective Study

Abstract Objectives To investigate the risk factors for surgical site infection together with the identification of the etiological pathogens and their antimicrobial susceptibility at King Khalid University Hospital, King Saud University, Riyadh, Kingdom of Saudi Arabia. Methods A prospective case series study conducted at King Khalid University Hospital to all patients admitted to the surgical wards during the period between January 1 st and September 30 th 2007. The demographic data, diagnostic criteria, associated risk factors and laboratory data including gram stain, culture results and antimicrobial susceptibility of swabs from the surgical sites were collected. Results Out of the one hundred and thirty one patients recruited in the study, nine patients showed evidence of sepsis yielding an infection rate of 6.8%. Emergency operations and associated diabetes showed significantly higher rates of infection compared to their counterparts. The most commonly isolated bacteria were: E. coli, Pseudomonas aurigenosa and Staphylococcus aureus. Conclusion The rate of surgical site infection was 6.8% which was comparable to that reported literature. E. coli was the most commonly isolated bacteria. Neither MRSA nor Acinetobacter species were common isolates. The rate of infection in diabetics and those who underwent emergency operations was significantly higher than others. Other comorbidities did not directly affect the rate of surgical site infection in our series.