Assessment of pro-inflammatory cytokines in sera of patients with hepatitis C virus infection before and after anti-viral therapy

Introduction: A number of cytokines have been implicated in hepatitis C virus (HCV)-related liver disease. This study aimed to assess the serum levels of pro-inflammatory cytokines in patients with HCV infection before (naïve) and after successful treatment (sustained responders) with Pegylated interferon and ribavirin. Methodology: The present study included 19 naïve HCV patients and 8 sustained responders. Additionally, 20 healthy individuals were included as a control group. The serum levels of the pro-inflammatory cytokines interleukin-8 (IL-8), IL-6, IL-10, IL-1β, and IL-12p70 were measured using flow cytometry. Results: The serum IL-8 levels were significantly higher in the naïve group (21.5±10.7 pg/mL; p = 0.02) than in the control group (14.1±1.7 pg/mL) and the sustained responder group (10.4±6.2 pg/mL; p = 0.002). The serum IL-6 levels were significantly higher in the naïve group (7.3±2.06 pg/mL; p = 0.02) than in the control group (5.9±1.01 pg/mL) whereas IL-6 in sustained responder group (6.4±1.5 pg/mL) was no different than naïve HCV patients or the controls. The serum IL-10 levels were significantly higher in the naïve group (4.42±0.64 pg/mL) than in the control group (3.6±0.34 pg/mL; p =0.0002) and not the sustained responder group (4.1±0.86 pg/mL). Moreover, the serum IL-12p70 levels were higher in the sustained responder group (3.43±0.84 pg/mL; p =0.05) than in the control group (2.76±0.83 pg/mL). There were no differences in the serum IL-1β levels among the groups. Conclusion: Successful anti-viral therapy against HCV was associated with significant reductions in the serum IL-8 levels and skewing of the pretreatment Th2 dominant immune response to the Th1 response.

Acute Back Pain: A Survey of Primary Health Care Physicians' Awareness and Knowledge of "Red Flag" Signs

Background:

The failure to detect “red flag” signs in patients presenting with acute low back pain can adversely affect the outcome of management. This can seriously affect the quality of life and productivity of the patient.

Objective:

The present questionnaire-based study was performed to assess the knowledge and awareness of red flag signs among primary health care physicians managing patients with acute back pain in Riyadh, Saudi Arabia.

Materials and Methods:

The study sample size was comprised of 80 subjects. The level of knowledge was assessed by means of a new structured self-administered questionnaire. The design of this questionnaire was based on the Agency for Health Care Research and Policy (AHCRP) guidelines for detection of red flag signs. Physicians were asked about red flag signs that indicate the presence of tumor, infection, spinal fracture, or cauda equina syndrome.

Results:

Sixty-eight (85% of total) physicians were aware of red flag signs. Of the 68 physicians who were aware of the red flag signs, 58 (72%) were aware of neurological deficit, 36 (45% of total) were aware of extremes of age (<10 years and >50 years), and 33 (41% of total) were aware of and routinely inquired about the history of spinal trauma, whereas only 24 (30% of total) were aware of and inquired about constitutional symptoms in their patients with acute back pain.

Conclusion:

Although low back pain is extremely common, knowledge and awareness of red flag signs of primary health care physicians managing patients with acute back pain in Riyadh appear to be inadequate. This indicates a lack of adherence to the international guidelines. Specific educational programs should target these deficiencies and increase awareness.

Rapid detection of circulating fibrocytes by flowcytometry in idiopathic pulmonary fibrosis

BACKGROUND:

Current protocols for detection of circulating fibrocytes (CFs) in peripheral blood described in various pulmonary and nonpulmonary disorders involve complex and time consuming, non standardized techniques.

OBJECTIVE:

Testing a method to rapidly detect and quantify CFs using whole blood lysis flow cytometry-based assay in patients with idiopathic pulmonary fibrosis (IPF) and healthy controls.

METHODS:

One milliliter of venous blood sample in ethylenediaminetetraacetic acid (EDTA) from 33 IPF patients and 35 healthy control subjects was collected. Using whole blood lysis method peripheral blood leukocytes were labeled with monoclonal antibodies for cell surface (CD34 and CD45) and intracellular markers (collagen-1) for flow cytometric analysis. CFs were defined as CD45⁺ cells coexpressing collagen-I and CD34 molecules.

RESULTS:

In 29 (87.8%) IPF patients and 10 (28.5%) control subjects, a well-defined highly granular CD45⁺ cell population was detected in dot plots generated by side scatter properties of CD45⁺ cells. These CD45⁺ cells were identified as CFs on the basis of coexpression of collagen-I and CD34; none of the other cell types in the peripheral blood were labeled with these monoclonal antibodies. In IPF patients the percentage of CFs was significantly higher compared to healthy controls (median (range): 1.37% (0.52-5.65) and 1.04% (0.1-1.84), respectively; P = 0.03).

CONCLUSIONS:

Whole blood lysis method combined with fluorescence-activated cell sorting (FACS) allows detecting a well-defined homogeneous population of CFs. This method is simple, reproducible, and provides an accurate and rapid estimation of CFs.

ESBL-producing Escherichia coli and Klebsiella pneumoniae at a tertiary care hospital in Saudi Arabia

INTRODUCTION

The increasing frequency and antibiotic resistance among extended-spectrum β-lactamases (ESBLs)-producing bacteria are posing a serious threat. This study sought to investigate the frequency and antibiotic susceptibility of ESBL-producing E. coli and K. pneumoniae at a tertiary care hospital.

METHODOLOGY

Data were collected from samples sent to the microbiology laboratory between 2006 and 2010 at King Khalid University Hospital, Riyadh. ESBLs were confirmed using Etest strips of cefotaxime/cefotaxime + clavulanic acid, ceftazidime/ceftazidime + clavulanic acid, and cefepime/cefepime + clavulanate.

RESULTS

Out of 17,105 samples, 1,076 (6.3%) ESBL-producing isolates of E. coli (808) and K. pneumoniae (268) were confirmed. Among these, 680 (63.2%) isolates were found in urine samples, followed by 287 (26.7%) in superficial swabs, deep wounds swabs, tissues and sterile body fluids, 71 (6.6%) in respiratory, and 38 (3.5%) in blood samples. The overall frequency rates of ESBL E. coli and K. pneumoniae were 6.6% and 5.5%, respectively. The frequency of ESBL-producing E. coli and K. pneumoniae increased significantly during the study period. E. coli resistance against cotrimoxazole was 71.1%, followed by ciprofloxacin (68.2%) and gentamicin (47%). Similarly, 62.7% of K. pneumoniae isolates were resistant to gentamicin, 59.5% to cotrimoxazole, and 49.8% to ciprofloxacin. There was no statistically significant change in antimicrobial resistance over the study period.

CONCLUSIONS

Although the frequency rates of ESBL-producing E. coli and K. pneumoniae increased, no change in the anti-microbial susceptibility was observed over the study period.

Screening for hen's egg and chicken meat specific IgE antibodies in Saudi patients with allergic disorders

BACKGROUND

Allergy to hen's egg and meat contributes significantly to the manifestations of food allergy all over the world.

OBJECTIVES

This study was performed to assess the presence of hen's egg and meat specific IgE antibodies among patients investigated for various allergic disorders.

METHODS

This is a retrospective study performed at King Khalid University Hosptial, Riyadh. Data from 421 patients with allergic disorders screened for food specific IgE antibodies between January 2009 and March 2011 were analyzed. Sixty (14.25%) patients including 42 males and 18 females with the mean age (sd) of 7.5 (7.4) years were found to have specific IgE antibodies against hen's egg and chicken meat. There were 56 (93.3%) children and 4 (6.7%) adult patients. Specific IgE antibodies were measured by radioallergosorbent test (RAST) using Pharmacia ImmunoCAP 250 analyzer.

RESULTS

Atopic dermatitis was the most common (55%) clinical condition. Out of the total 60 patients harboring hen's egg and chicken meat specific IgE antibodies high levels of egg white, yolk and chicken meat specific IgEs were detected in 58 (96.6%), 37 (61.6%) and 6 (10%) patients respectively. Both the egg white and yolk antibodies coexisted in 35 (58.3%) patients.

CONCLUSION

Sensitization against hen's egg was higher compared to the chicken meat. Egg white sensitization higher than the egg yolk particularly in Saudi children with food related allergic disorders.

Immunological evaluation of β-thalassemia major patients receiving oral iron chelator deferasirox

OBJECTIVE

To determine the immune abnormalities and occurrence of infections in transfusion-dependent β-thalassemia major patients receiving oral iron chelator deferasirox (DFX).

STUDY DESIGN

An observational study.

PLACE AND DURATION OF STUDY

Hematology Clinics, King Khalid University Hospital, Riyadh, Saudi Arabia, from July to December 2010.

METHODOLOGY

Seventeen patients with β-thalassemia major (12 females, median age 26 years) receiving deferasirox (DFX) for a median duration of 27 months were observed for any infections and had their immune status determined. Immune parameters studied included serum immunoglobulins and IgG subclasses, serum complement (C3 and C4) and anti-nuclear antibody (ANA) level, total B and T-lymphocytes, CD4+ and CD8+ counts, CD4+/CD8+ ratio, and natural killer (NK) cells. Immunological parameters of the patients were compared with age, gender, serum ferritin level and splenectomy status. Lymphocyte subsets were also compared with age and gender matched normal controls.

RESULTS

A considerable reduction in serum ferritin was achieved by DFX from a median level of 2528 to 1875 μmol/l. Serum IgG levels were increased in 7 patients. Low C4 levels were found in 9 patients. Total B and T-lymphocytes were increased in 14 patients each, while CD4+, CD8+ and NK cells were increased in 13, 12 and 11 patients respectively. Absolute counts for all lymphocyte subsets were significantly higher compared to the normal controls (p ² 0.05 for all parameters). Raised levels of IgG were associated with older age, female gender, splenectomized status and higher serum ferritin levels but this did not reach statistical significance except for the higher ferritin levels (p=0.044). Increased tendency to infections was not observed.

CONCLUSION

Patients with β-thalassemia major receiving DFX exhibited significant immune abnormalities. Changes observed have been described previously, but could be related to DFX. The immune abnormalities were not associated with increased tendency to infections.

Cytokine gene polymorphisms of TNFα, IL-6, IL-10, TGFβ and IFNγ in the Saudi population

Studies have demonstrated associations between cytokine gene polymorphisms and ethnicity. In the present work the authors examine polymorphisms in the genes encoding interleukin-6 (IL-6), IL-10, interferon-gamma (IFNgamma), tumour necrosis factor-alpha (TNFalpha) and transforming growth factor-beta (TGFbeta1) using the polymerase chain reaction sequence-specific primer (PCR-SSP) method in 150 healthy unrelated Saudis, and results compared with those from other studied populations. The genotype distributions were consistent with the Hardy-Weinberg equilibrium, and the genotype frequencies observed among Saudis showed both similarity and difference to other populations. The most notable difference was in the distribution of IL-6, where the Saudi population showed a lower CG genotype frequency compared with White American (22% vs. 39.2%, P = 0.004), Italian (22% vs. 50%, P < 0.0001) and Brazilian (22% vs. 40.8%, P < 0.0001) populations. The study population also showed a higher frequency of the IL-6 GG genotype compared with White Americans (72% vs. 45.1%, P < 0.0001), Italians (72% vs. 41%, P < 0.0001) and Brazilians (72% vs. 49.3%, P < 0.0001). These results may have significant clinical relevance to the understanding of prevalent diseases in Saudi Arabia.

Q fever: a neglected zoonosis in Saudi Arabia

BACKGROUND AND OBJECTIVES

Infection due to Coxiella burnetii (C burnetii), the causative agent of Q fever is rarely sought for in clinical practice. This study was performed to detect C burnetii infection in patients with pyrexia of undetermined cause (PUC).

DESIGN AND SETTINGS

This is a prospective study conducted at King Khalid University Hospital, Riyadh be.tween March 2011 and January 2013.

PATIENTS AND METHODS

A total of 3 mL venous blood was collected from 51 patients with PUC at King Khalid University Hospital, Riyadh. This group of patients included 30 males and 21 females (mean age 33.9 [21.3] years) with the history of febrile illness ranging between 4 and 8 weeks. A control group of 50 healthy individuals comprising 39 males and 11 females (mean age 27 [9] years) was also included in the study. Detection of phase II C burnetii-specific IgG antibodies was performed by immunofluorescence assay, and a titer of > 1:64 was considered positive.

RESULTS

Phase II C burnetii-specific IgG antibodies were detected in 18 (35.2%) patients out of the total 51 tested. Two (4%) individuals out of 50 in the control group tested positive for anti-C burnetii IgG antibodies. The proportion of positive results among the patients was significantly higher than the controls (P < .0002, 95% CI, 15.09-46.25). The antibody titer range was between 1:128 and 1:1024 where 6 patients had titers of 1:256, 5 had 1:512, 4 had 1024, and 3 had 1:128.

CONCLUSION

The evidence of C burnetii infection in a sizable number of patients emphasizes the need for inclusion of serologic investigations for Q fever in patients with PUC.

Garlic and onion sensitization among Saudi patients screened for food allergy: a hospital based study

BACKGROUND

Detection of specific IgE antibodies against food materials indicates allergic sensitization. Some very widely consumed foods materials such as garlic and onion have rarely been investigated for their allergenic potential.

OBJECTIVES

To assess the presence of garlic and onion specific IgE antibodies in patients investigated for food allergy.

METHODS

Radioallergosorbent test (RAST) results of 108 patients with clinical suspicion of food allergy who were specifically screened for garlic and onion specific IgE antibodies along with other food allergens were analyzed retrospectively at King Khalid University Hospital between January 2008 and April 2009. This group of patients included 73 males and 35 females with mean age 27+13.2 years. Estimation of garlic and onion specific IgE antibodies was performed by radioallergosorbent test (RAST) using Pharmacia ImmunoCAP 250 analyzer.

RESULTS

Out of the 108 patients 15 (13.8%) had garlic and onion specific IgE antibodies in their sera. Garlic specific IgE antibodies with the RAST scores between one to four were present in 14 and onion specific IgE were detected in 13 patients. For garlic specific IgEs majority of patients (08) had RAST score of one (0.35-0.69 kU/L) and for onion specific IgE antibodies seven patients had RAST score of two (0.70-3.49 kU/L). Among these patients 12 (80%) were found to have coexisting specific IgE antibodies against garlic and onion.

CONCLUSION

The presence of garlic and onion specific IgE antibodies in a sizeable number of patients indicate sensitization and allergenic potential of these food materials.

Cytokine gene polymorphisms and serum cytokine levels in patients with idiopathic pulmonary fibrosis

Background

Studies have demonstrated associations between cytokine gene polymorphisms and the risk of idiopathic pulmonary fibrosis (IPF). We therefore examined polymorphisms in the genes encoding interleukin (IL)-6, IL-10, interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and transforming growth factor-beta 1 (TGF-β₁), and compared the serum levels of these cytokines in IPF patients and healthy controls. Furthermore, we examined the association of the studied genotypes and serum cytokine levels with physiological parameters and the extent of parenchymal involvement determined by high-resolution computed tomography (HRCT).

Methods

Sixty patients with IPF and 150 healthy controls were included. Cytokine genotyping was performed using the polymerase chain reaction sequence specific primer (PCR-SSP) method. In a subset of patients and controls, serum cytokine levels were determined by enzyme-linked immunosorbent assay.

Results

There was no difference between IPF patients and controls in the genotype and allele distributions of polymorphisms in TNF-α, IFN-γ, IL-6, IL-10, and TGF-β₁ (all p > 0.05). The TNF-α (−308) GG, IL-6 (−174) GG and CG, and IL-10 (−1082, -819, -592) ACC ATA genotypes were significantly associated with HRCT scores (all p < 0.05). IL-10 (−1082, -819, -592) ACC haplotype was associated with the diffusion capacity of the lung for carbon monoxide, and ATA haplotype was associated with the partial pressure of oxygen (PaO₂) (all p < 0.05). The TGF-β₁ (codons 10 and 25) TC GG, TC GC, CC GG and CC GC genotypes were significantly associated with the PaO₂ and HRCT scores (p < 0.05). The TGF-β₁ (codons 10 and 25) CC GG genotype (5 patients) was significantly associated with higher PaO₂ value and less parenchymal involvement (i.e., a lower total extent score) compared to the other TGF-β₁ genotypes (81.5 ± 11.8 mm Hg vs. 67.4 ± 11.1 mm Hg, p = 0.009 and 5.60 ± 1.3 vs. 8.51 ± 2.9, p = 0.037, respectively). Significant differences were noted between patients (n = 38) and controls (n = 36) in the serum levels of IL-6 and IL-10 (both, p < 0.0001), but not in the levels of TNF-α and TGF-β₁ (both, p > 0.05).

Conclusion

The studied genotypes and alleles do not predispose to the development of IPF but appear to play an important role in disease severity. Our results suggest that the TGF-β₁ (codons 10 and 25) CC GG genotype could be a useful genetic marker for identifying a subset of IPF patients with a favorable prognosis; however, validation in a larger sample is required.

Pattern of patch test reactivity among patients with clinical diagnosis of contact dermatitis: a hospital-based study

BACKGROUND AND OBJECTIVES

Contact allergy is associated with a significant morbidity all over the world. This study was performed to investigate the pattern of sensitization by contact allergens in the local population.

DESIGN AND SETTING

Retrospective study to investigate patch test reactivity among patients with clinical diagnosis of contact dermatitis who were referred to the allergy clinic at the King Khalid University Hospital, Riyadh, between April 2008 and March 2010.

PATIENTS AND METHODS

Of the 196 patients referred to the allergy clinic over the 2-year period, 91 (46.4%) patients reacted to one or more patch test allergens, and these patients were included in this study. The study group included 82 (91.1%) of Saudi nationality and 9 (8.9%) patients of other nationalities. The patch test was performed using the T.R.U.E TEST, containing 24 allergens/allergen mixes.

RESULTS

Of the 91 cases who reacted positively to one or more allergens, 67 (73.6%) were females with a mean age of 37 (8.3 years) and 24 (26.4%) were males with a mean age of 34 (11.6 years). Thirty-three (36.2%) patients reacted to nickel sulfate, 14 (15.3%) to p-phenylenediamine, 13 (14.2%) to p-tert-butylphenol-formaldehyde resin, 13 (14.2%) to thimerosal, and 9 (9.8%) to colophony. Reactivity against the rest of the allergens was not remarkable. A significantly higher percentage of females reacted to nickel sulfate (84.8% vs 15.2% in males;P=.0001), p-tert-butylphenol-formaldehyde resin (92.3% vs 7.7%; P=.0001), and thimerosal (76.9% vs 23.1%;P=.03).

CONCLUSIONS

Patch test reactivity to nickel sulfate was high. The pattern of contact allergy observed in this study indicates the need for large-scale investigations to identify local allergens responsible for contact allergy and for formulation of policies directed towards avoidance of exposure.

Human leucocyte antigens: their association with end-stage renal disease in Saudi patients awaiting transplantation

Most patients with chronic renal failure develop end-stage renal disease (ESRD) that requires renal transplantation. This study investigates the possible associations between human leucocyte antigen (HLA) Class I and Class II molecules with ESRD. Genotyping data (HLA) obtained between 2005 and 2009 on 235 unrelated Saudi patients (147 males, 88 females; mean age: 58 +/- 7 years) with ESRD awaiting renal transplantation were assessed retrospectively at the King Khalid University Hospital. Data were compared with the results on 60 normal, healthy, unrelated Saudi individuals (37 males and 23 females; mean age: 51 +/- 5 years). HLA Class I and Class II antigens were detected by lymphocytotoxicity and a polymerase chain reaction (PCR) method using DNA sequence-specific primers. Although present in small numbers, HLA Cw2 was found in significantly fewer patients (n = 11; 4.68%) compared to normal subjects (n = 9; 15%) and was found to confer protection against ESRD (P = 0.005; relative risk [RR]: 3.594, 95% confidence interval [CI]: 1.415-9.126). Among the HLA Class II antigens, HLA DQB1*03(8) was detected more frequently in the patient group (n = 65; 27.6%) than in the normal controls (n = 9; 15%) and was positively associated with risk of ESRD (P = 0.04; RR: 0.462, 95% CI: 0.215-0.991). No significant differences were observed between the two groups in respect of HLA-A2, HLA-B50(21), HLA-B51(5) and HLA-Cw7 (HLA Class I), and HLA-DRB1*04, HLA-DRB1*07 and HLA-DQB1*02 (HLA Class II). Occurrence of the most frequent HLA alleles was no different between the ESRD group and the controls. The protective role of HLA-Cw2 and the marginal susceptibility associated with HLA-DQBI*03(8) for ESRD requires further investigation.

Modifications influencing Widal test reactivity in a novel microplate assay

Reliability of the Widal tube agglutination test has been the subject of many controversies over the years. This study was performed to assess the effect of certain modifications on the performance of Widal test in a novel microplate assay. Sera from 37 patients (21 males; 16 females) (mean age 28 +/- 7 years) were tested in the Immunology Unit at King Khalid University Hospital, Riyadh. Among them were 26 patients with suspected typhoid fever and 11 had bacteriologically confirmed diagnosis of Salmonella infection. The modifications included either the use of 0.5% bovine serum albumin (BSA), absorption of sera with sheep red blood cells (SRBC) or heat inactivation of sera. Compared with Widal tube agglutination test, microplate assay with SRBC absorption of the sera from patients with suspected typhoid fever was not only associated with enhancement of detection titers for both H (p < or = 0.001) and O (p < or = 0.005) Salmonella agglutinins but also the percentage of reactivity. The presence of BSA augmented detection titers for Salmonella H agglutinins (p < or = 0.02) only. Heat inactivation of sera however was found to be associated with reduction in the detectable titers for both H (p < or = 0.03) and O (p < or = 0.01) agglutinins. Increased titers of Salmonella agglutinins were also evident in 11 patients with confirmed diagnosis of Salmonella infection. The novel microplate agglutination assay using the SRBC absorption was associated with enhancement in Widal test reactivity and appears to be a useful alternative for the diagnosis of Salmonella infection.

Salmonella isolates’ serotypes and susceptibility to commonly used drugs at a tertiary care hospital in Riyadh, Saudi Arabia

Introduction: Resistance of Salmonella to therapeutic agents currently being used for treatment of Salmonella infections is emerging as a global problem. This study aimed to assess the prevalence of Salmonella serotypes and their susceptibility patterns to commonly used drugs for treatment of Salmonella infections including quinolones. Correlation between nalidixic acid susceptibility of these isolates and their ciprofloxacin minimum inhibitory concentrations was also sought. Methodology; Salmonella isolates (n=213) were collected between January 2007 and May 2009 at King Khalid University Hospital in Riyadh, Saudi Arabia. The isolates were serotyped and their susceptibilities to commonly used first-line anti-Salmonella drugs (ampicillin, ceftriaxone, trimethoprim/sulfamethoxazole, nalidixic acid and ciprofloxacin) were determined using the automated Microscan system, the Kirby-Bauer disk diffusion method, and E-test. Results: The most frequently detected serotype was D1 (37%) followed by the serotypes, B (24%) and C1 (11%). Non-typable Salmonella isolates detected using available conventional Salmonella anti-sera were (11%). Overall resistance rates to nalidixic acid, ampicillin, trimethoprim/sulfamethoxazole and ceftriaxone were 99/213 (46%), 43/213 (20%), 34/213 (16%) and 7/213 (3%), respectively. Of the total isolates, 117 (55%) had a ciprofloxacin MIC of < 0.125 µg/ml and among these 105 (90%) were susceptible to nalidixic acid. The remaining 96 (45%) isolates had a ciprofloxacin MIC of ≥ 0.125 µg/ml and among them, 83 (86.5%) were resistant to nalidixic acid. Conclusions: The majority of Salmonella isolates in this study were non-typhi serotypes. Significantly higher proportions of Salmonellae were resistant to nalidixic acid and ciprofloxacin and a vast majority of nalidixic acid resistant organisms exhibited decreased susceptibility to ciprofloxacin.

Detection of Salmonella typhi agglutinins in sera of patients with other febrile illnesses and healthy individuals

BACKGROUND AND PURPOSE

Widal test is frequently applied for the detection of Salmonella agglutinins to diagnose Salmonella enterica serotype Typhi infection. There are however a number of controversies challenging the diagnostic utility of this test. This study was performed to determine the prevalence of Salmonella agglutinins in patients with other febrile illnesses and healthy blood donors.

MATERIALS AND METHODS

Sera from 50 healthy blood donors were compared for the presence of Salmonella agglutinins in various groups of patients with other febrile illnesses using Widal test in the division of Serology and Immunology at King Khalid University Hospital, Riyadh. The patient groups of other febrile illnesses included infections with Beta-hemolytic streptococcus (n = 50), Brucella (n = 46), Helicobacter pylori (n = 24), Treponema pallidum (n = 30), Toxoplasma (n = 44), and other parasites (n = 20).

RESULTS

Majority of the patients and normal individuals were tested positive for Widal test at dilution of less than 1 : 40 both for the O (62.5%) and H (64.6%) antigen. A decreasing trend in Widal reactivity was observed with increasing dilutions of the serum samples. At 1 : 160 titer, which is generally considered as a cut off point for positive Widal test, 6.4 and 11% individuals had positive Widal test for O and H Salmonella antigens, respectively.

CONCLUSION

Detection of a significant number of positive Widal tests in conditions where it is expected to be nonreactive appears to be a serious problem in making a correct diagnosis of typhoid fever, thus challenging the diagnostic utility of the Widal test.

Antenatal screening for syphilis at a tertiary care hospital in Riyadh

BACKGROUND

Routine serologic screening for syphilis is recommended for all pregnant women in Saudi Arabia. This study examined the results of routine antenatal syphilis screening at a tertiary care hospital in Riyadh.

PATIENTS AND METHODS

The results of rapid plasma reagin (RPR) tests were compiled for in 3270 pregnant women tested between October 2002 and March 2003 at King Khalid University Hospital. Any RPR reactivity observed in neat or diluted serum was considered positive and confirmed by a Treponema pallidum hemagglutination (TPHA) test.

RESULTS

Syphilis screening constituted 87% of RPR tests requested for all reasons during the study period. The majority of women (73%) were screened between 15 to 22 weeks of gestation. Of the 3270 women tested only one was found to have syphilis, a prevalence rate of 0.03%.

CONCLUSION

The prevalence of syphilis is extremely low in the antenatal care population at King Khalid University Hospital in Riyadh. This calls for a nation-wide survey to assess the need for continuation of antenatal syphilis screening with regards to its potential benefits and cost effectiveness in the Kingdom of Saudi Arabia.

Serial evaluation of percentage of activated T-lymphocytes in peripheral blood of human immunodeficiency virus infected individuals as a prognostic marker

OBJECTIVE

Immune activation often associated with human immunodeficiency virus (HIV) infection is characterized by increasing number of peripheral blood T-lymphocytes expressing HLA-DR molecule. This study was performed to investigate the changes in the percentage of activated lymphocytes in the peripheral blood of HIV infected patients on antiretroviral therapy.

METHODS

Routine flow cytometry data for peripheral blood lymphocyte subsets were analyzed in 11 HIV infected hemophilia patients (mean age 27 +/- 7) at approximately 6 monthly intervals from 1996 to 2002 in the Division of Immunology, King Khalid University Hospital, Riyadh, Kingdom of Saudi Arabia. The number of data sets for each individual was variable, ranging between 5-13. Percentages of each lymphocyte subset were extracted and correlations were sort by using linear regression analysis.

RESULTS

Proportion of activated T-lymphocytes in the peripheral blood was initially high. Over a period of 2-5 years the percentage of T-lymphocytes, expressing HLA-DR molecule was found to have decreased significantly (P < or =0.0001) in all the patients most probably as a result of antiretroviral therapy. There was no statistically significant change in the proportion of any other lymphocyte subtype studied. The reduction in the percentage of HLA-DR+ T-lymphocyte population inversely correlated with CD4/CD8 ratios in 8 and for the CD4+ lymphocyte proportions with 5 out of 11 patients, whereas positive correlation for CD8+ lymphocyte proportions was noted in 4 patients.

CONCLUSION

These findings confirm immune activation in HIV infection with the increasing percentage of HLA-DR+ T-lymphocytes in the peripheral blood. Declining activated T-lymphocyte proportion in the peripheral blood and its inverse correlation with CD4/CD8 ratio may be more sensitive in detection of changes in CD4+ and CD8+ lymphocyte populations in HIV infection serving as a prognostic marker.

Increased prevalence of asthma in Saudi Arabia

BACKGROUND

Bronchial asthma is among the most common chronic illnesses of childhood. A number of reports in the recent past suggest that the prevalence of asthma is increasing globally.

OBJECTIVE

To investigate the changing prevalence of asthma in the Kingdom of Saudi Arabia.

SUBJECTS AND METHODS

Two populations of schoolchildren between the ages of 8 and 16 years were studied using an internationally designed protocol in 1986 and 1995. The questionnaire used in these studies was very similar to the one used in the International Study of Allergy and Asthma in Childhood. A total of 2,123 school-children in 1986 (Jeddah and Riyadh) and 1,008 schoolchildren in 1995 (Hail and Gizan) were enrolled in the surveys. These cross-sectional studies of randomly selected schoolchildren were statistically analyzed using ANOVA and a Z test.

RESULTS

The comparison of data between Riyadh versus Hail (inland desert dry environment) and Jeddah versus Gizan (coastal humid environment) revealed that the prevalence of asthma in the similar populations increased significantly from 8% in 1986 to 23% in 1995 (P < .0001). Likewise, the prevalence of allergic rhinitis also increased from 20% to 25% (P < .003) since 1986. However, no significant change in the prevalence of eczema (from 12% to 13%) was noted between 1986 and 1995.

CONCLUSIONS

The study indicates that there was a significant increase in the prevalence of bronchial asthma and, to a lesser extent, in the prevalence of allergic rhinitis in the Kingdom of Saudi Arabia during this 9-year period. The study also revealed increased exposure to environmental factors such as tobacco smoke and indoor animals in Saudi houses. It seems that the continuing changes in contemporary life may well have contributed to the increased prevalence of asthma in the country.

Circulating adhesion molecules in sarcoidosis

Sarcoidosis is a disease of unknown etiology characterized by non-caseating granulomata together with a number of systemic abnormalities. We have recently shown these include increased expression of the integrins CD11/CD18 on peripheral blood leucocytes. Here we have measured serum levels of the adhesion molecules intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) in 23 patients and 14 normal controls using antigen capture sandwich ELISAs. Median circulating E-selectin levels in the patients were nearly three times those of the controls (P < 0.0001, Mann-Whitney U-test), whilst ICAM-1 but not VCAM-1 levels were only slightly elevated. These results show that endothelial cell activation and shedding of E-selectin into the circulation are additional features of the pathology of sarcoidosis.

A new method for measuring clustering in suspension between accessory cells and T lymphocytes

Specifying the molecular basis and clinical significance of cluster formation between antigen-presenting cells and T lymphocytes will be important in many areas of immunology. In this paper we describe a novel and reproducible technique for measuring cluster formation in suspension between purified human blood monocytes and purified autologous T lymphocytes, and its application to determining the effects of recall antigens and mitogen. Blood monocytes and T lymphocytes from eight normal subjects were separately prelabelled with two different carbocyanine dyes prior to co-culture in suspension with or without antigen (PPD, SKSD) or mitogen (PHA). At 24 h the co-cultures were examined for cluster formation by ultraviolet microscopy and flow cytometry. Control experiments showed that the carbocyanine dyes were non-toxic in vitro, that cell labelling was stable for culture periods up to 120 h, and that the two dyes did not leak from cell to cell. By this technique we measured the proportion of monocytes clustering one or more T lymphocytes in the presence and absence of recall antigen or PHA. There was a close correlation between visual and flow cytometric measurement of monocyte: T lymphocyte clustering (p < 0.001) as well as a close relationship between the ability of the two recall antigens to increase the extent of clustering above baseline (p < 0.001). Antigen-increased cluster formation did not correlate with baseline clustering, unlike PHA-increased clustering, which was related to baseline levels (p = 0.02), suggesting the operation of distinct mechanisms. The method is applicable to measuring cell-cell associations in suspension during extended periods of culture, as well as for the study of agents which might modify intercellular adhesion processes.

Increased CD11/CD18 expression on peripheral blood leucocytes of patients with sarcoidosis

Sarcoidosis is a multisystem disease of unknown etiology characterized by non-caseating granulomata, formed mainly from macrophages surrounded by lymphocytes and plasma cells. Using a novel method for the preparation of blood leucocytes for flow cytometry, we report increased expression of LeuCAMs (CD11/CD18) on peripheral blood leucocytes of 11 Caucasian and 10 Afro-Caribbean patients with sarcoidosis compared with age-, sex- and race-matched controls. Whilst the percentages of the cells expressing CD11/CD18 were no different, the density, expressed as mean fluorescence intensity (MFI), was greater for all leucocytes in sarcoids than in normal individuals. The expression of intercellular adhesion molecule-1 (ICAM-1), a ligand for LFA-1 which is expressed on all leucocytes, was not significantly different from normal, whereas HLA-DR was expressed more intensely on sarcoid monocytes (P less than 0.01) and blood lymphocytes (P less than 0.005) than control cells. Our findings are consistent with leucocyte activation although we were unable to confirm reports of elevated tumour necrosis factor-alpha (TNF-alpha) in the patients' plasma using an ELISA. Increased expression of adhesion molecules on peripheral blood leucocytes may play a role in the cellular extravasation, aggregation, and granuloma formation seen in sarcoidosis.

Alveolar macrophage accessory cell function in bronchial asthma

The capacity of peripheral blood monocytes and alveolar macrophages (AM) obtained by bronchoalveolar lavage (BAL) to present recall antigens, namely, tuberculin purified protein derivative (PPD) or streptokinase-streptodornase (SKSD), to highly purified autologous T-cells has been studied in 11 asthmatic and 11 healthy, nonatopic normal subjects. In the asthmatic group, AM accessory cell function was variable, and most subjects were unable to present either recall antigen as effectively as blood monocytes, although one asthmatic subject demonstrated larger proliferative responses than blood monocytes for both antigens. AM accessory cell activity was not antigen-specific, and there was a correlation between accessory cell efficacy for the two antigens (r = 0.92; confidence interval, 0.53 to 0.98). Furthermore, a correlation existed between the percentage lymphocyte count in the BAL fluid and the ratio of macrophage to monocyte antigen-presenting capability for both PPD (r = 0.92; 95% confidence interval, 0.83 to 0.99) and SKSD (r = 0.90; 95% confidence interval, 0.45 to 0.98). In the normal subjects, AM were also unable to act effectively as accessory cells for the presentation of PPD and SKSD in the majority of subjects. No correlation existed between the percentage lymphocytes in BAL fluid and the ratio of AM to monocyte accessory cell function. These results suggest an association between AM accessory function and the presence of BAL lymphocytes in bronchial asthma.

A method of preparing blood leucocytes for flow cytometry which prevents upregulation of leucocyte integrins

LeuCAM (CD11/CD18) cell-surface antigens are easily upregulated on cell manipulation ex vivo. A procedure for preparing leucocytes, in which human blood is immediately treated ex vivo with buffered formaldehyde and then the erythrocytes and platelets are removed by lysis and differential centrifugation, has been successfully applied to the analysis of LeuCAM antigen expression by flow cytometry. We show that the increased expression of monocyte CD11/CD18, which occurs when mononuclear leucocytes are separated by a standard Lymphoprep density gradient separation, can be avoided if cells are fixed immediately. Following this fixation polymorphs are unable to upregulate CD11/CD18 in response to fMLP stimulation in vitro. The technique produces lymphocyte, polymorph and monocyte populations that can be clearly defined on the basis of forward scatter and side scatter, and preserves the expression of various surface antigens; the percentages of gated lymphocytes expressing CD3, CD4, and CD8 were similar to those obtained using a commercial fixing and lysis solution. The processing does not render cells permeable to antibodies, as evidenced by our failure to stain cells with antibodies to intracellular antigens. We believed the method to be useful for measuring CD11/CD18 expression on blood leucocytes from normal or pathological specimens and to have application to the measurement of other cells surface antigens which may also be upregulated by the separation procedures.