Purified Protein Derivative Positivity Research Articles

Real time endobronchial ultrasound transbronchial needle aspiration for the diagnosis of tuberculous intrathoracic lymphadenopathy: Saudi Arabian Western region experience.

To assess the utility of endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) for presumptive tuberculosis (TB) patients with intrathoracic enlarged lymph nodes in a country with low to moderate TB incidence. Thirty-one patients with clinical features of TB and intrathoracic lymphadenopathy, who had EBUS-TBNA sampling and final confirmation of intrathoracic TB lymphadenopathy, were retrospectively reviewed over an 8-year period. Routine clinical and laboratory evaluations including computerized tomography scans were performed before the EBUS-TBNA. Sociodemographic characteristics, clinical profile, pathological, and microbiological findings were collected. The EBUS-TBNA confirmed TB diagnosis in 26 (83.9%) subjects with a consistent pathological finding or positive culture of Mycobacterium tuberculosis. Pathological analysis had findings consistent with TB in 25 (80.6%) patients. Culture of the EBUS-TBNA sample was positive for Mycobacterium tuberculosis in 12 (38.7%) patients. Other supportive investigations like purified protein derivative (PPD) skin test was positive in 28 (90.3%) participants. Overall, the sensitivity of the EBUS-TBNA alone was 83.9%. No complications were recorded during the procedure. The EBUS-TBNA aspirate culture positivity was significantly related to having a larger size lymph node (p=0.048) only, while PPD positivity was significantly related to baseline and clinical features of the participants. The EBUS-TBNA demonstrated effective utility and safety in the evaluation and diagnosis of intrathoracic TB lymphadenopathy among individuals with compatible symptoms in a country with low-moderate TB-incidence.

Purified Protein Derivative Response in Type 1 Diabetics

Aim: The aims of our study were to identify the role of suppressor T1 helper cells in the immunopathogenesis of type 1 diabetes mellitus (T1D) and to investigate the purified protein derivative (PPD) response, which is a delayed type of skin sensitivity response that develops secondarily to the effect of the T1 helper cell response. Method: Twenty-four newly diagnosed patients with T1D were included in the study (12 girls, 12 boys), and 30 (18/12) age/sex matched healthy children were included as controls. All patients underwent the PPD skin test (TST) in the first diagnostic 24–48 h (study group-1) and again 1 month after diagnosis (study group-2). The PPD response was compared with the response of healthy children. The lower limit of PPD positivity was accepted as ≥ 10 mm. Results: The mean PPD induration value taken in the study group-2 was statistically greater than both the study group-1 and the control group PPD (p=0.014, p=0.001). Regarding the increase in duration, the PPD positivity rate was statistically higher after the first month than in the control group (p= 0.005) and the initial PPD positivity rate (p=0.023). Conclusion: Interesting results emerged for the PPD response of the study group-2, because the PPD positivity rate increased over time.

Correlation of single-nucleotide polymorphism at interferon-gamma R1 (at Position - 56) in positive purified protein derivative health workers with COVID-19 infection.

The aim of the present study was to investigate the susceptibility of purified protein derivative (PPD) plus health-care workers to SARS-CoV-2 (COVID-19). For this reason, single-nucleotide polymorphism (SNP) of interferon-gamma (IFN-γ) gene at position +2109 and IFN-γ receptor 1 (R1) at position -56 was assessed in PPD plus group before and after COVID-19 infection (2017-2018; 2020-2021). The selected study cases (n = 100) that were working in tuberculosis (TB) unite (5-10 years) with PPD positivity >15 mm (16-20 mm) were included in this investigation. Sampling was done twice, once before and after the COVID-19 pandemic. Group A contains 50 samples collected from the GenBank TB laboratory that belong to TB staff before the pandemic (2017-2018). The other sample (Group B; 2021) was collected from the same unite during the COVID-19 pandemic. The SNP in the IFN-γ gene (+2109; 670 bp) and IFN-γ R 1 (-56; 366 bp) was performed using a specific primer and the polymerase chain reaction products were digested using restriction enzyme Fau I and Bts I, respectively. Statistical analyses were used to obtain the frequency of alleles among all studied cases. The confidence intervals (CIs) and t-test were calculated using the SPSS and GraphPad Prism software. In overall, the most frequent genotype in Group A was AA (41/50; 82%) and Group B was 76% (38/50) in position + 2109 (odds ratio [OR] = 0.69, 95% CI, 0.26-1.83, and P = 0.46). Although in position -56, the most frequent genotype in Group A was TT (35/50; 70%) which significantly was than Group B TT (15/50; 30%) (OR = 0.184, 95% CI, 0.78-0.43, and P = 0.00). The frequency of allele A was more in both groups at position + 2109 (OR = 0.815, 95% CI, 0.23-2.86, and P = 0.75), whereas the dominate allele at position -56 was T in Group A (OR = 1.37, 95% CI, 0.62-3.02, and P = 0.42). No significant differences were observed in + 2109 in genotype among Group A and B. The main differences were seen in IFN-γ R1 at position (-56) between Group A and B. Hence, the IFN-γ R1 may play important role in COVID-19 infection. However, more study is needed to clear the IFN-γ correlation to COVID-19 infection.

The relationship between lymphocyte subsets, nutritional status and tuberculin reactivity in continuous ambulatory peritoneal dialysis and hemodialysis patients

AimSkin test anergy is common in patients with uremia and during maintenance hemodialysis treatment. However, up to date only one study concerning skin test in peritoneal dialysis patients has focused on the issue. Our cross-sectional controlled study was conducted to analyze the correlation of purified protein derivative (PPD) test response with demographical features, nutritional parameters and the distribution of peripheral blood lymphocyte subsets in peritoneal dialysis and hemodialysis patientsPatients and methodsStable 30 hemodialysis (HD) patients (16 men, 14 women) and 30 continuous ambulatory peritoneal dialysis (PD) patients (17 men, 13 women) were included. Thirty healthy cases (15 men, 15 women) with a mean age of 32.4 ± 9.4 constituted the control group.ResultsIn the HD group, 14 patients (46.6%) were PPD positive, and ın the PD group 16 patients (53.3%) were PPD positive. In the PPD-positive HD patients 64.2% (9/14), and in the PPD-positive PD patients 62.4% (10/16) had an induration of 10 mm or greater. In the control group, 21 of 30 patients (70%) were PPD positive. Comparison of both HD and PD groups with the control group showed significant differences in PPD reactivity (p < 0.01). Albumin levels were significantly high in the control groups (p < 0.01), and cholesterol levels were significantly high in the PD and the control groups (p < 0.05). Transferrin levels were significantly high in the PD (p < 0.01). The lymphocyte counts were significantly high in the control group compared to the HD patients (p < 0.05). The lymphocyte subset percentages CD19 were high in the control groups (p < 0.05), and CD16/56 was significantly high in the PD groups (p < 0.05). All the parameters were also similar between PPD-positive and -negative same groups.ConclusionThe prevalence of PPD positivity was lower in the PD and HD groups. The PPD test responses were not related to the peripheral lymphocyte counts, subsets and malnutrition parameters.

Tuberculosis prevalence among university freshmen in Zhengzhou, China, during 2004-2013.

Tuberculosis (TB) is a major public health concern worldwide, and spreads more easily in densely populated areas such as school campuses. The aim of this study was to determine the prevalence of positive TB skin tests among freshmen, i.e. newly-enrolled college students, in Zhengzhou City, China. We reviewed the data of purified protein derivative (PPD) skin tests in 656,212 freshmen in 2004-2013. A positive test showed a diameter of swelling ≥ 5 mm. The PPD positive rate was 40.69 %, with a prevalence of 146.29 per 100,000. During the 10-year study period, the rate of students with positive PPD test increased from 34.19 % in 2004 to 40.69 % in 2013. The positive PPD rate was significantly higher in males than in females (41.68 % vs 39.61 %, P<0.0001), and in rural compared with urban areas (42.04 % vs 38.03 %, P<0.0001). These findings indicated a high prevalence of PPD positivity among participants during the study period, with an increasing trend. Therefore, this population needs to be targeted by TB prevention and control programs.

Mantoux test revisited: Variability in reading tuberculin test in pediatric population.

Mantoux test aids in the diagnosis of tuberculosis (TB), however its application and interpretation are dependent on multiple factors. A prospective study enrolling 400 children (aged 2-12) suspected to have tuberculosis. All participants received Mantoux test with two different strengths (1 TU and 5 TU) of Purified Protein Derivative (PPD) on different forearms. The test was read by two readers after 48 ± 2 and 72 ± 2 hours. Primary outcome was difference in the size of induration when read by two readers (interobserver variability). Secondary outcomes were difference in the size of induration at different intervals, with different strengths of PPD and percentage positivity of Mantoux test in TB patients. Statistically significant difference was seen in the size of induration when read by two different readers, with fair to moderate agreement when read at 48 and 72 hours (1 TU: p = 0.002, k = 0.52 and p = 0.1, k = 0.73 respectively, 5 TU: p = 0.001, k = 0.39 and p = 0.0009, k = 0.33 respectively). Tendency of under-reading occurred when size of induration was close to significant level (10-14 mm). Size of induration was similar when read at 48 or 72 hours (1 TU: p = 0.9, 5 TU: p = 1.0). Mantoux positivity rate in patients with TB was more with 5 TU as compared to 1 TU (61.2% vs. 16.3%). There is significant interobserver variability with a tendency to under-read around the cutoff point. The use of 5 TU PPD at 48 hours by a trained physician can aid in early and more reliable diagnosis of TB.

Clinical Significance of Incidentally Detected Torus Tubarius Calcification.

Calcification of the torus tubarius has been rarely reported in the literature. Histopathologic studies have previously described cases of Eustachian tube calcification and cite an association with increasing patient age. The purpose of this study was to examine the prevalence of torus tubarius calcification and potential clinical significance on an unrestricted patient population using thin-section computed tomography (CT), which has not been previously reported. After the institutional review board approval, 1571 consecutive patients who underwent noncontrast head CT between January 2011 and July 2011 were retrospectively reviewed for torus tubarius calcification. Images were acquired at 1.25-mm slice thickness using a 64-detector row CT. Medical records were reviewed for chronic medical conditions including chronic kidney disease, alcoholism, autoimmune conditions, endocrine disorders, elevated alkaline phosphatase levels, history of otitis media, purified protein derivative positivity, history of head and neck surgery and radiation, and human immunodeficiency virus infection. Motion-limited studies and patients with limited clinical data were excluded. Statistical analyses were performed using the independent sample t test and Fisher exact test. Ten (0.6%) of 1571 patients had torus tubarius calcification, of which 7 (70%) were unilateral, and 3 (30%) were bilateral calcification. There was no significant association between torus tubarius calcification and common medical disorders including endocrine disorders, human immunodeficiency virus, chronic kidney disease, alcoholism, purified protein derivative positivity, history of head and neck surgery or radiation, and autoimmune diseases. Based on the largest series to date on an unrestricted population using thin-section CT imaging, calcification of the torus tubarius is a rare entity with an overall prevalence of 0.6%. Although the clinical significance remains uncertain, there is no significant association between torus tubarius calcification and common medical conditions.

The utility of routine tuberculosis screening in county hospital patients with uveitis

Background/aimTo evaluate the utility of tuberculosis (TB) screening in diagnosing ocular TB in uveitis patients in a government-funded hospital.MethodsThe charts of 142 consecutive patients seen during August 2011–July 2012 at...

Predicting Surgical Outcomes in Pediatric Cervicofacial Nontuberculous Mycobacterial Lymphadenitis

We examined surgical outcomes in children with cervicofacial nontuberculous mycobacterial lymphadenitis and attempted to identify predictors of complications. A retrospective chart review from 2 tertiary pediatric centers was used to identify .11 presentation or operative variables (age at surgery, gender, symptom duration, pain, violaceous skin changes, skin breakdown, fluctuance, purified protein derivative positivity, operative procedure, use of nerve integrity monitoring, and use of skin flap advancement) and to compare these to 5 postoperative complications (facial nerve dysfunction [paresis or paralysis], poor scarring, recurrence, wound infection, and wound dehiscence without infection). The 45 patients analyzed for presentation or operative variables (28 female, 17 male; average age, 31.2 months) typically presented with painless masses averaging 8.2 weeks in duration, along with violaceous skin changes in 29 of the 45 cases (64%) and skin breakdown in 9 cases (20%). The surgical procedures included parotidectomy with or without selective lymphadenectomy in 38 of the 45 cases (84%) and lymphadenectomy alone in 7 cases (16%). Skin resection and cervicofacial advancement flap reconstruction was performed in 20 cases (44%). Nerve integrity monitoring was utilized in 32 cases (71%). In the 44 patients analyzed for postoperative complications, we found facial nerve paresis in 14 (31.8%), poor scarring in 9 (20.5%), wound infection in 6 (13.6%), recurrence in 4 (9.1%), and facial nerve paralysis in 2 (4.5%). Nine of the 14 cases (64.3%) of initial facial nerve paresis resolved. At final follow-up, facial nerve paresis persisted in 5 of the 14 children (35.7%) with initial postoperative paresis and in 1 of the 2 children (50.0%) with initial postoperative paralysis. Facial nerve paralysis persisted in the other child with initial postoperative paralysis. Overall, 6 of these 7 patients (85.7%) with persistent facial nerve dysfunction had follow-up of less than 1 month. All transient and permanent facial nerve dysfunction was in the distribution of the marginal mandibular nerve only. No statistically significant predictors of complications were identified. We report acceptable but not insignificant rates of marginal mandibular distribution facial nerve injury, poor scarring, wound infection, and recurrence following resection of cervicofacial nontuberculous mycobacterial lymphadenitis in children that must be discussed with patients and parents before operation. No presentation or operative variables predicted the complications.

Resposta de testes de hipersensibilidade tardia utilizando PPD e outros antígenos em crianças e adolescentes saudáveis e infectados pelo HIV-1 e vacinados com BCG

Among HIV-1-infected patients, CD4+ T cell counts are well-established markers of cell-mediated immunity. Delayed-type hypersensitivity (DTH) skin tests can be used to evaluate in vivo cell-mediated immunity to common antigens. DTH responses to tuberculin purified protein derivative (PPD), sporotrichin, trichophytin, candidin and streptokinase/streptodornase antigens were assessed. Thirty-six HIV-1-infected children/adolescents and 56 age- and sex-matched HIV-1/HIV-2-seronegative participants were tested. All participants had a BCG scar. Fisher's exact test was used to evaluate significant differences between groups (p<0.05). The main characteristics of the HIV-1 patients were as follows: median age 8.1 years; 20/36 were males; 35 were vertical transmission cases; 34 were AIDS cases under antiretroviral therapy; median viral load = 3.04 log10 copies/ml; median CD4+ T cell count = 701 cells/μl. A total of 25% (9/36) and 87.5% (49/56) of HIV-1-infected and healthy participants, respectively, displayed DTH reactivity to at least one antigen (p<0.001). Among HIV-1-infected participants, reactivity to candidin predominated (8/36, 22.2%), while PPD positivity prevailed among healthy participants (40/56, 71.4%). PPD reactivity in the HIV-1-positive group was 8.3% (p<0.01). The median PPD induration was 2.5mm (range: 2-5mm) in the HIV-1 group and 6.0 mm among healthy participants (range: 3-15 mm). There was no correlation between PPD positivity and age. No correlation between CD4+ T cell counts and DTH reactivity was observed among HIV-1-infected patients. DTH skin test responses, including PPD reactivity, were significantly lower among HIV-1-infected participants compared to healthy controls, which likely reflects advanced disease and T cell depletion.

Purified Protein Derivative Response in Juvenile Idiopathic Arthritis

To examine the purified protein derivative (PPD) response that develops depending upon Th1 immune response in children with juvenile idiopathic arthritis (JIA). PPD skin test was performed in 115 children with JIA who were vaccinated with bacillus Calmette-Guerin (BCG), and then they were compared to the PPD response of 45 healthy children of the same age who were vaccinated with BCG. Children with a PPD induration > or = 5 mm were accepted as PPD-positive. PPD induration > or = 10 mm was accepted as a limit for suspecting tuberculosis. PPD induration size and PPD positivity rates (PPD > or = 5 mm) of children with JIA were significantly lower than those of healthy children. The mean of PPD induration size was significantly lower (p < 0.0001) in patients with either 1 BCG vaccine (3.7 +/- 3.6) or more than 1 BCG vaccine than controls with either 1 BCG vaccine (7.10 +/- 3.2) or more than 1 BCG vaccine (10.05 +/- 4.1). PPD was positive in 35.9% of patients with JIA vaccinated once (n = 32), in 50% of patients with JIA vaccinated more than once (n = 13), in 82.1% of controls vaccinated once (n = 23), and in 88.2% of controls vaccinated more than once. This result was statistically significant (patients, p = 0.03; controls, p = 0.039). It was determined that neither the activity of the disease nor the use of corticosteroid and methotrexate affected the PPD response. The response to PPD, which is one of the Th1 cell-type responses, was significantly lower in BCG-vaccinated children with JIA compared to healthy children.

P022 - Attenuated response to purified protein derivative test in patients with inflammatory bowel disease

Introduction: Detecion of latent tuberculosis (LTB) is important before stating immunosupression or biological agents in patients with inflammatory bowel disease (IBD). The purified protein derivative (PPD) skin test is the most widely used method which detect LTB. Since the introduction immunosupression and biological treatment in IBD many cases of tuberculosis (TBC) have been observed. Especially in populations with high prevalence. Most of these cases occur in the first months of treatment suggesting reactivation of LTB. Objective: To evaluate the response to PPD in patients with IBD and to compare it with that of control subjects. Methods: We evaluated a total 44 IBD patients (25 patients with Crohn’s disease, 16 patients with ulcerative colitis and 2 patients with indeterminate colitis), 14 men and 30 women. None of the patients were using immunosuppressives nor biological agents. Forty-six healthy controls (10 men and 36 women) were included. PPD 5 U was applied using the Mantoux method, and skin reaction was measured at 72 hours. The reaction was considered positive if induration was 5mm. Results: There were no signifant differences in age, sex, history of Bacille Camette-Guerin vaccination between two groups. The median size of the PPD induration in patients with IBD was significantly less than that in the control group (7.5 vs 12.3mm, p 0.05). There were significantly more anergic tests in pateints with IBD than in control (29.5% vs 13%, p < 0.05). Conclusion: In Turkey where tuberculosis is relatively frequent, we observed a lower frequency of PPD positivity and high incidence of anergy in IBD patients compared to controls. T-lymphocyte mediated immunity defects in IBD patients, especially in Crohn’s disease may explain the lower frequency of PPD positivity in these patients. In IBD patients, other than PPD test, new screening methods needed to evaluate latent TBC before starting immunosupressive or biological treatments.

The results of purified protein derivative test in ankylosing spondylitis patients: clinical features, HRCT results and relationship with TNF-blocker usage

In this study, we evaluated the clinical features, treatment modalities, including TNF-blockers, purified protein derivative (PPD) test, chest X-ray and HRCT results in our AS patients. We evaluated the clinical features, disease activity and PPD results in 88 AS patients (72 males, 16 females, mean age: 38.3+/-10) diagnosed at our center. 119 RA, 28 SLE and 27 gouty arthritis patients followed up at the same time period were taken as the control group. The mean disease duration in AS patients was 12.6+/-8.3 years. The frequency of PPD positivity in AS patients (77.3%) was similar to that in gouty arthritis (70.4%) patients; and significantly higher than the frequency in SLE (21.4%) and RA (35.3%) patients (P values<0.001). There was a chest X-ray abnormality in 20 AS patients (22.7%). When subjects (11 patients, 12.5%) with apical fibrosis, aspergillosis, previous or active TB on chest X-ray and/or HRCT were compared to others; it was observed that they were older (P<0.001), had longer disease duration (P=0.006); and less chest expansion (P=0.01). Fifty patients were administered TNF-blockers. The PPD test was positive in 38 of patients (76%) using TNF-blockers. All of these patients were given isoniazid prophylaxis. After a median follow up of 18 months, TB did not develop. In Turkey which is a country with a relatively high incidence of TB, in spite of a higher frequency of PPD positivity in AS patients compared to RA and SLE patients, TNF-blockers did not result in any TB with suitable prophylaxis.

Absence of Relationships Between Tuberculin Responses and Development of Adult Asthma With Rhinitis and Atopy

To investigate the relationship between tuberculin skin responses and the development of adult asthma, rhinitis, and atopy. Two hundred fourteen patients with mild-to-moderate asthma accompanied with rhinitis and 220 normal volunteers underwent a medical history, chest radiography, allergen skin-prick testing (SPT), bovine Mycobacterium tuberculosis vaccine (BCG) scar identification, purified protein derivative (PPD) tuberculin skin testing, serum-total and serum-specific IgE measurements, and bronchial provocation (provocative dose of histamine causing a 20% fall in FEV(1) [PD(20)]). Thirty-one normal volunteers (14.1%) and 168 asthma-rhinitis subjects (78.5%) had one or more positive skin test results (p < 0.0001). Neither the presence of a BCG scar nor a history of BCG vaccination had a significant effect on atopy in either group. The rate of PPD positivity had no statistical difference between atopy and nonatopy in both groups. In multivariate logistic regression analysis, the odds ratio for tuberculin reactivity was not related to the level of serum-total IgE nor to the level of serum-specific IgE to Dermatophagoides pteronyssinus (DP) and Dermatophagoides farinae (DF), skin response to DP and DF, and PD(20). Overall, no significant correlations were found between tuberculin skin reactivity and log serum-total IgE or PD(20). There is no relationship between history of tuberculosis infection, tuberculin responses, and development of adult bronchial asthma, allergic rhinitis, and atopy. Our study suggests that the protection provided by intradermal BCG vaccination in infants to prevent atopic diseases may be limited in early childhood, when a substantial memory of cellular immune modulation still exists.

A Tuberculosis Event on a Navy Assault Ship

A tuberculosis event occurred on a U.S. Navy amphibious assault ship in September 2003. The event was signaled by a jump in monthly purified protein derivative positivity rates. A baseline new reactor rate of 0 to 1% suddenly jumped to 6.3%, prompting screening of the entire crew and embarked Marines. Ultimately, a total of 31 Navy and 17 Marine new reactors was identified. This represented 2.4% of the Navy crew and 1.2% of embarked Marines. Only 1 of 31 Navy cases involved an officer. Two Navy, male, enlisted berthing areas showed a statistically significantly increased odds ratio for infection risk. Despite intensive investigation, no active case of tuberculosis was ever identified. After treatment of new reactors with isoniazid, the ship's monthly new reactor rate returned to baseline. This case illustrates the principles and pitfalls of respiratory disease control at sea.

COINCIDENT FILARIAL, INTESTINAL HELMINTH, AND MYCOBACTERIAL INFECTION: HELMINTHS FAIL TO INFLUENCE TUBERCULIN REACTIVITY, BUT BCG INFLUENCES HOOKWORM PREVALENCE

The prevalence of helminth and tuberculosis infections is high in South India, whereas Bacille-Calmette-Guerin (BCG) vaccine efficacy is low. Our aim was to determine whether concurrent helminth infection alters the ability to mount a delayed-type hypersensitivity response to tuberculin. In a cross-sectional study in southern India, individuals 6-65 years of age were screened for intestinal helminths, circulating filarial antigenemia, tuberculin reactivity, active tuberculosis, and history of BCG vaccination; 54% were purified protein derivative (PPD) positive, 32% had intestinal helminth infection, 9% were circulating filarial antigen positive, and 0.5% had culture-confirmed active tuberculosis. Only age and BCG vaccination were significantly associated with PPD reactivity; however, BCG vaccination was associated with a lower prevalence of hookworm infection relative to those without prior BCG vaccination. Neither intestinal helminth infection nor filarial infection was associated with diminished frequencies of PPD positivity. Our findings suggest that preceding helminth infection does not influence significantly the delayed-type hypersensitivity response to tuberculin.

Influence of Bacillus Calmette‐Guèrin vaccination at birth and 2 months old age on the peripheral blood T‐cell subpopulations [gamma/delta (γδ) and alpha‐beta (αβ) T cell

The neonatal immune system is immature and may be affected by Bacillus Calmette-Guèrin (BCG) vaccine. We investigated the influence of BCG given at two different ages on the peripheral blood (PB) T-cell subpopulations. Forty full term healthy newborns were randomly chosen. Twenty of them were vaccinated with BCG at birth (group I) and the remaining at the age of 2 months (group II). The cell analysis were carried out before (pre-BCGI and pre-BCGII), and 2 months after (post-BCGI and post-BCGII) the vaccination. The analysis of the gamma/delta and alpha/beta T-cell receptor (TCR) antigens was done by two-colour flowcytometer. The purified protein derivative (PPD) response was investigated 2 months after vaccination. The results showed that although T-cell (TCR+ cell) counts showed no difference in PB before and after vaccination in both study groups, the total lymphocyte and non-T cell (TCR- cell) populations increased significantly whereas alphabetaT-cell population significantly decreased after vaccination. On the contrary, gammadeltaT-cell counts in PB increased significantly 2 months after vaccination in group I but not in group II. Total lymphocyte and non-T cell counts in vaccinated infants at 2 months of age (post-BCGI) were significantly higher than in unvaccinated infants of the same age whereas alphabetaT-cell count in vaccinated infants was significantly low. However, total T-cell and gammadeltaT-cell counts showed no difference. PPD positivity was similar in both study groups (61% in group I, 66% in group II). Neither alphabetaT- nor gammadeltaT-cell counts were different in PPD positive and PPD negative infants. Our study shows that BCG causes marked quantitative changes in the PB T-cell subpopulations in young infants.

Viral hepatitis and other infectious diseases in a homeless population.

To determine the prevalence of four common infectious diseases-hepatitis B, hepatitis C, human immunodeficiency virus (HIV), and tuberculosis-as well as co-infection rates and risk factors in a homeless population. The prevalence of infectious diseases, especially viral hepatitis, among the homeless population is largely unknown. This study consists of a retrospective analysis of the history and laboratory data collected from all homeless veterans admitted to a Veterans Administration (VA) domiciliary from May 1995 to March 2000. Of the homeless veterans admitted to a VA domiciliary program, 597 of 829 were screened for markers of all four infectious diseases. The overall prevalence of anti-hepatitis C virus (HCV) antibody, and positive result for purified protein derivative (PPD), anti-HIV antibody, and hepatitis B surface antigen (HbsAg) were 41.7%, 20.6%, 1.84% and 1.17%, respectively. At least one of the four markers was positive in 52.6% and more than one in 12%. Co-infection with HCV occurred commonly in veterans who were positive for anti-HIV (72.7%) and HBsAg (57.1%). Four self-reported major risk factors (intravenous drug use, alcohol abuse, previous imprisonment, and prior stay in a shelter) were evaluated. Multivariate analysis indicates that intravenous drug use and anti-HBs reactivity are independent risk factors for HCV infection, HCV infection for anti-hepatitis B surface antibody reactivity, and older age for PPD positivity. Chronic hepatitis C and co-infections are common among the homeless population. Patients infected with HIV and hepatitis B virus frequently are co-infected with HCV. Infections frequently are associated with certain identifiable risk factors.

Use of purified protein derivative to assess the risk of infection in children in close contact with adults with tuberculosis in a population with high Calmette-Guérin bacillus coverage.

Household contacts <15 years of age of adults with tuberculosis (TB) attending a reference center in Aracaju, Sergipe, Northeast Brazil. To assess the use of purified protein derivative (PPD) and frequency of infection in children with high Calmette-Guérin bacillus (BCG) coverage who were recently exposed to TB. Cross-sectional study of 141 exposed household contacts <15 years of age and 506 nonexposed neighborhood controls. Children were examined and assessed for degree of exposure to index cases, BCG vaccination and scar and were tested with PPD. Exposed children were younger and less up to date in their vaccination schedule than controls (P < 0.05). BCG had been given to 95.6% of exposed children and 97.4% of controls, but only 80.9% of exposed vs. 88.5% of controls had a scar (P < 0.05). Scar sizes of exposed children were smaller (medians, 4.5 and 7 mm, respectively; P < 0.05). Children had lower weight for age z scores and height than the National Center for Health Statistics standards. Exposed children had lower weight for age z scores than controls (P < 0.05). Sixty-seven (47.5%) exposed children and 18 (3.6%) controls had PPD readings of >10 mm. Positivity and induration sizes increased with age, although this was significant only in the controls. The presence of a BCG scar was not associated with having a positive PPD. The degree of exposure was an important factor for PPD positivity; 66 (60.6%) of the 109 children with close exposure were positive compared with 1 (3.1%) of 32 with less intimate exposure. PPD indurations among close contacts were also larger than those with restricted exposure and controls (16.3, 11 and 9.4 mm, respectively; P < 0.05). PPD positivity was associated with the quantification of acid-fast bacilli in the adult; 38.5% of contacts with adults with sputum with (+) were positive, compared with 42.3% of those with (++) and 58.4% with (+++) (P < 0.05). PPD is a useful test to identify children infected with TB independently of whether they had received BCG or not. Children exposed to adults with TB are at high risk of infection. The risk of infection is associated with the intimacy of contact and the number of bacilli expectorated in sputum.

Establishing an employee baseline purified protein derivative status in the division of immigration health Service Processing Centers.

While the incidence of reportable tuberculosis in United States born persons declined, the number of cases among foreign-born persons increased by 6 percent in 1998. The Immigration and Naturalization Service (INS) processes about 95,000 undocumented aliens annually from countries with a high prevalence of tuberculosis. An effort was made to establish a baseline Purified Protein Derivative (PPD) status of employees of the Division of Immigration Health (DIH) and INS, Services Processing Centers (SPC). This was achieved through a special operation (project) of a one time, two-step, mass PPD testing of all SPC employees on all eleven sites in the United States and Puerto Rico. A reading of > 10mm was considered positive. The operation was optional and open to all SPC employees. Exclusion criteria for the study included a history of PPD skin testing within six months of the operation, past history of positive PPD test and past history of tuberculosis. Preliminary results from El Paso SPC, Texas, which is the largest SPC, showed that of the 148 employees which were tested (67 percent of all employees), 17 (11 percent) were PPD positive. Security officers constituted 100 percent of all positive cases. Eighty-one percent of the employees at El Paso are security officers, eighty-seven percent of whom participated in the study. Only 20 (23 percent) of administrative staff participated in the study. Results from El Paso are suggestive of differences in the pattern PPD positivity among SPC employees. The complete results of the study should provide sound evidence for formulating appropriate policies for establishing an effective employee tuberculosis prevention and surveillance program in the Service Processing Centers.