Assessing the Detection of Middle East Respiratory Syndrome Coronavirus IgG in Suspected and Proven Cases of Middle East Respiratory Syndrome Coronavirus Infection.

Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe respiratory disease with significant mortality. Two testing methods are currently used for MERS-CoV diagnostics: nucleic acid detection (the gold standard) and serological analysis. In this study, we evaluated the detection of MERS-CoV-IgG in suspected and proven cases of MERS-CoV infection. We enrolled 174 patients: 113 had respiratory symptoms/suspected MERS-CoV infection, 31 had confirmed influenza A or B infection, 23 had a recent confirmed MERS-CoV infection, and 7 had confirmed MERS-CoV infection 1 year before. All underwent MERS-CoV RNA and MERS-CoV-IgG testing. Thirty patients were found to be MERS-CoV RNA positive; however, during serological analysis, only 6 (3.4%) patients were positive for MERS-CoV-IgG, 1 (0.6%) patient was equivocal, and 167 (96%) patients were negative. Among the serological positives, four were recently MERS-CoV RNA positive and two were MERS-CoV RNA negative. No cross-reactivity to influenza A or B was detected. Based on the lack of correlation between nucleic acid and serological analysis, we conclude that MERS-CoV-IgG testing may not be suitable for diagnosing acute infection or estimating its prevalence during an outbreak. In addition, our findings show that MERS-CoV-IgG may not have significant value in determining disease severity or prognosis.

Prevalence and characterization of occult hepatitis B infection among blood donors in central Saudi Arabia.

OBJECTIVES: To evaluate the prevalence of occult hepatitis B viral infections (OBIs)  among blood donors considering the clinical and epidemiological importance of identifying OBIs. METHODS: A cross-sectional study conducted at King Khalid University Hospital, Riyadh, Saudi Arabia between January 2011 and January 2012. Blood donors (n=8501) were screened for Hepatitis B virus surface antigen (HBsAg) and hepatitis B core antibodies (HBcAb). All HBsAg-negative and HBcAb-positive samples were tested further for hepatitis B surface antibodies (HBsAb), hepatitis B virus (HBV)-DNA, and HBV genotyping.   RESULTS: Of the 8501 serum samples tested, 56 (0.7%) were positive and 8445 (99.3%) were negative for HBsAg. Among the HBsAg-negative samples, 198 (2.3%) were positive for HBcAb and these patients were suspected to have OBIs. Among the HBcAb-positive samples, 119 (60.1%) were positive while 79 (39.9%) were negative for HBsAb. Analysis of HBV-DNA for the suspected OBIs showed that 17 out of 198 samples (8.6%) yielded positive results, and all of them were HBsAb-negative. The viral load was low (less than 20-186 IU/mL) in all OBIs. Hepatitis B virus genotyping showed that 15 out of 17 samples (88.2%) were genotype D, and the other 2 samples (11.8%) were genotype E.  CONCLUSION: The prevalence of OBIs among blood donors in Riyadh was 0.2%. Therefore, it is recommended that HBV molecular testing should be incorporated with serological assays for screening of blood donors.

Late-onset prosthetic valve endocarditis caused by nontoxigenic Corynebacterium diphtheriae.

In developed countries, Corynebacterium diphtheriae infection is rare due to efficient immunization programs. However, cases of nontoxigenic strains of C. diphtheriae infections, including endocarditis, have been reported recently. Although the incidence remains low, these infections are associated with high morbidity and mortality. This report describes the first and atypical case of bacteremia and endocarditis caused by nontoxigenic C. diphtheriae var. gravis after introduction of immunization in the Kingdom of Saudi Arabia (KSA).

Prevalence of HBV, HCV, HIV-1, 2 and HTLV-I/II infections among blood donors in a teaching hospital in the Central region of Saudi Arabia.

OBJECTIVE: Several infectious diseases are transmissible by blood transfusion, especially viral infections. The most common blood-transmitted viruses are hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). These viruses cause fatal, chronic and life-threatening disorders. The prevalence of these viruses varies by nationality and geography. The purpose of this study was to establish the current prevalence of hepatitis viruses (B and C) and human retroviruses (HIV-1, 2 and human T-lymphotropic virus type I and II, HTLV-I /II) among blood donors at King Khalid University Hospital (KKUH), Riyadh, Kingdom of Saudi Arabia (KSA). METHODS: Serological markers of HBV, HCV, HIV 1, 2 and HTLV-I/II were studied in 24173 (23952 males and 221 females), 20423 Saudi and 3750 non-Saudi blood donors, using commercially available kits, over a period of 3 years from January 2000 to December 2002 at KKUH, Riyadh, KSA. The prevalence of confirmed-positive test results of these viruses was evaluated among different gender, ages and nationalities. RESULTS: During the study period, prevalence rates of HBV and HCV infections were 1.5% and 0.4%, and zero for retroviral infections. The prevalence was not significantly higher in male than in female donors. Hepatitis B surface antigen (HBsAg) and anti-HCV positivity tend to increase with increase in age. The prevalence of HBsAg and anti-HCV positivity was significantly more prevalent among non-Saudi compared to Saudi donors. CONCLUSION: This study highlights the prevalence rates of HBV and HCV among different groups. The prevalence varies from one group to another, being the lowest among Saudi and young donors. Therefore, extensive recruitment of Saudi and young donors should help ensure a long-term increase in the blood supply without jeopardizing safety.

Hepatitis G virus in Saudi blood donors and chronic hepatitis B and C patients.

INTRODUCTION: Screening blood donors for blood-borne pathogens is very critical for the recipient's safety. Similar to hepatitis B and C infections, hepatitis G infection is transmitted through contaminated blood and causes acute and chronic hepatitis. Previous reports have shown that the prevalence of hepatitis G virus (HGV) RNA among healthy Saudi donors was 1%-2%. However, the exposure rate of this virus has never been studied. We hypothesized that the prevalence of HGV infection may have changed overtime due to socio-economic and environmental factors. Since hepatitis B and C infections are endemic in Saudi Arabia, we investigated the exposure rate of HGV infection in healthy donors and chronically infected hepatitis B and C patients. METHODOLOGY: A prospective study was done on healthy donors and patients with chronic HBV and HCV infections. Hepatitis B and C viral loads were measured by real-time polymerase chain reaction. HGV exposure rate was evaluated by detection of HGV antibodies. RESULTS: Analysis of samples from healthy donors (n = 210), chronic HBV+ patients (n = 169), and chronic HCV+ patients (n = 105) showed that nine samples (4.3%), seven samples (4.1%), and four samples (3.8%) were positive for HGV antibodies, respectively. The non-significant difference in the exposure rates of HGV between the study groups may indicate that HGV infection occurs independent of HBV or HCV infections. CONCLUSIONS: We showed for the first time that the exposure rate of HGV infection among the Saudi population is 4.3%, and we recommend HGV screening for all blood donors.

Correlation between hepatitis B surface antigen titers and HBV DNA levels.

BACKGROUND/AIM: To assess the correlation between serum HBsAg titers and hepatitis B virus (HBV) DNA levels in patients with hepatitis B envelop antigen-negative (HBeAg -ve) HBV genotype-D (HBV/D) infection. PATIENTS AND METHODS: A total of 106 treatment- naïve, HBeAg -ve HBV/D patients were included; 78 in the inactive carrier (IC) state and 28 in the active hepatitis (AH) stage. HBV DNA load and HBsAg titers were tested using TaqMan real-time polymerase chain reaction (PCR) and automated chemiluminescent microparticle immunoassay, respectively. RESULTS: The median (range) log10 HBsAg titer was significantly lower in the IC group compared with AH group, 3.09 (-1 to -4.4) versus 3.68 (-0.77 to 5.09) IU/mL, respectively; P < 0.001. The suggested cutoff value of HBsAg titer to differentiate between the two groups was 3.79 log10 IU/mL. In addition, there was a significant positive correlation between HBsAg and HBV DNA levels in the whole cohort, AH, and IC groups (r = 0.6, P < 0.0001; r = 0.591, P = 0.001; and r = 0.243, P = 0.032, respectively). CONCLUSION: Serum HBsAg titers may correlate with HBV DNA in treatment-naïve HBeAg -ve HBV/D patients, and supports the use of HBsAg levels in clinical practice as a predictor of serum HBV DNA levels.

Predictors of pulmonary involvement in patients with extra-pulmonary tuberculosis.

OBJECTIVES: The aim of this study is to assess the value of chest radiographs (CXRs) and sputum examinations in detecting pulmonary involvement of tuberculosis (TB) in patients with extra-pulmonary tuberculosis (EPTB). MATERIALS AND METHODS: A retrospective analysis was performed among 248 EPTB patients with culture-proven diagnosis of tuberculosis seen between January 2001 and December 2007 at a tertiary teaching hospital, Riyadh, Saudi Arabia. Demographics, clinical, laboratory and radiological findings were reviewed and assessed. This study was approved by the hospital ethics and research committee. RESULTS: One hundred twenty five of 233 EPTB patients (53.6%) had abnormal CXR findings. There was a significant difference in the occurrence of positive sputum culture results between patients with abnormal CXR findings (30/57) and those with normal CXR findings (4/17) (P = 0.04). Of 17 HIV-negative/unknown HIV-status EPTB patients with normal CXR results, 4 patients (23.5%) had positive sputum culture results. Intrathoracic lymphadenopathy (P < 0.001), pleural TB (P < 0. 001) and disseminated TB (P = 0.004) were associated with an increased risk of abnormal CXR findings. Patients with cough (52.9%), weight loss (41.2%) and night sweats (26.5%) are more likely to have positive sputum culture results. CONCLUSION: CXR findings are predictive of positive sputum culture results. However, the rate of normal CXR among EPTB patients with positive sputum culture results was relatively high. Therefore, respiratory specimen cultures should be obtained in TB suspects with a normal CXR to identify potentially infectious cases of TB.

Panton-Valentine leukocidin Staphylococcus aureus osteomyelitis of the femur in a Saudi child.

Staphylococcus aureus producing Panton-Valentine leukocidin (PVL) is well recognized to cause severe skin and soft tissue infections. Recently, it has been increasingly recognized as causing life-threatening musculoskeletal infection. We reported previously 3 children who had osteomyelitis caused by methicillin resistant Staphylococcus aureus. We report and discuss a case of Methicillin sensitive staphylococcus aureus encoding the PVL genes isolated from a child with acute osteomyelitis from Saudi Arabia.

Extra-pulmonary tuberculosis in Saudi Arabia.

Studies from developed countries have reported that extra-pulmonary tuberculosis (EPTB) is on the rise due to the human immunodeficiency virus (HIV) epidemic. However, similar studies from high-burden countries with low prevalence of HIV like Saudi Arabia are lacking. Therefore, we conducted this study to investigate demographic and clinical characteristics of patients with pulmonary and extra-pulmonary tuberculosis. A retrospective analysis was carried out on all patients (n=431) with a culture - proven diagnosis of tuberculosis seen at University teaching hospital, Riyadh, Saudi Arabia from January 2001 to December 2007. A total of 183 (42.5%) pulmonary tuberculosis (PTB) and 248 (57.5%) extra-pulmonary TB (EPTB) cases were compared in terms of age, sex, and nationality. There were 372 Saudis (SA) (86.3%) and the remaining non-Saudis (NSA) 59 (13.7%). The age distribution of the PTB patients had a bimodal distribution. EPTB was more common at young age (20-29 years). The proportion of EPTB cases was significantly higher among NSA patients (72.9%) compared to SA patients (55.1%). Females had higher proportion (59.5%) of EPTB than males (55.6%). The most common site was lymph node tuberculosis (42%). In conclusion, our data suggest that EPTB was relatively common in younger age, female gender and NSA. Tuberculosis (TB) control program may target those populations for EPTB case-finding.