352. Evaluation of Serial Serum (1-- >3)-b-D-glucan Assay in Patients with Invasive candidiasis, Pneumocystis Jiroveci Pneumonia and Aspergillosis

Background

Serum (1-- >3)-b-D-glucan (BDG) assay is a noninvasive serological marker that can be used as an adjunct to the diagnosis of invasive candida infections, Pneumocystis jiroveci pneumonia (PJP) as well as aspergillosis. There is limited data in serial monitoring of serum BDG in those fungal infections after treatment was initiated. Figure 1:Serial serum BDG levels of each subject after treatment initiation

Methods

This is a cross-sectional study of subjects with proven fungal infection (invasive candidiasis, aspergillosis or PJP) and with increased serum BDG >500 pg/ml who were admitted to University of Kentucky (UK) hospitals or clinics from 01/2012 to 01/2021. It was approved by institutional IRB. We compared at least two measures of the serum β-D-glucan levels obtained within two to eight weeks after initial diagnosis to evaluate the levels of β-D-glucan during and post-treatment. A decrease in BDG level is defined as any value below 500 pg/ml; normal serum BDG level as < 80 pg/ml.

Results

Of 26 subjects included in this cohort, 14 (51.8%) subjects had invasive candidiasis, six (22.2%) subjects had PJP, and six (22.2%) subjects had invasive aspergillosis. Twelve patients did not have a repeat BDG level after at least two separate levels with >500 pg/ml. Ten (38.5%) subjects had a decline in BDG level 2-3 weeks after starting treatment. Serum BDG level did not return to within normal limits at week 4 of treatment except one patient.

A repeat serum BDG level was seen decline at three weeks of treatment in four of six (66.6%) subjects with PJP, six weeks of treatment in three of six (50.0%) subjects with invasive aspergillosis and 8 weeks of treatment in six of 14 (42.8%) patients with invasive candidiasis. Two subjects had persistent elevation of BDG 8 weeks after treatment. (Figure 1)

Conclusion

Serial serum BDG level was not routinely done for monitoring the treatment response in this cohort. There was no linear decline in serum BDG level even after appropriate treatment in invasive fungal infections. A decline in serum BDG level was best observed among subjects with PJP pneumonia. It appears that the duration of a decline in serum BDG level was shorter in patients with PJP and longer in patients with invasive candidiasis.

Disclosures

All Authors: No reported disclosures.

Root Canal Treatment Survival Analysis in National Dental PBRN Practices

Few studies have examined the longevity of endodontically treated teeth in nonacademic clinical settings where most of the population receives its care. This study aimed to quantify the longevity of teeth treated endodontically in general dentistry practices and test the hypothesis that longevity significantly differed by the patient's age, gender, dental insurance, geographic region, and placement of a crown and/or other restoration soon after root canal treatment (RCT). This retrospective study used deidentified data of patients who underwent RCT of permanent teeth through October 2015 in 99 general dentistry practices in the National Dental Practice-Based Research Network (Network). The data set included 46,702 patients and 71,283 RCT permanent teeth. The Kaplan-Meier (product limit) estimator was performed to estimate survival rate after the first RCT performed on a specific tooth. The Cox proportional hazards model was done to account for patient- and tooth-specific covariates. The overall median survival time was 11.1 y; 26% of RCT teeth survived beyond 20 y. Tooth type, presence of dental insurance any time during dental care, placement of crown and/or receiving a filling soon after RCT, and Network region were significant predictors of survival time (P < 0.0001). Gender and age were not statistically significant predictors in univariable analysis, but in multivariable analyses, gender was significant after accounting for other variables. This study of Network practices geographically distributed across the United States observed shorter longevity of endodontically treated permanent teeth than in previous community-based studies. Also, having a crown placed following an RCT was associated with 5.3 y longer median survival time. Teeth that received a filling soon after the RCT before the crown was placed had a median survival time of 20.1 y compared to RCT teeth with only a crown (11.4 y), only a filling (11.2 y), or no filling and no crown (6.5 y).

742 Transurethral LASER Ablation (TULA): A Safe and Well Tolerated Procedure for The Treatment of Bladder Tumours Up To 4cm In Diameter in An Outpatient Setting

Aim

Traditionally the management of recurrent non-muscle invasive bladder cancer (NMIBC) involves rigid cystoscopy and bladder biopsies/tumour resection under general/regional anaesthesia. As a result, many frail patients endure frequent anaesthetics and therefore are at increased risk of adverse outcomes including cognitive decline. Discontinuation of anti-platelet/anti-coagulation is not required for TULA. An outpatient TULA service was recently started at our trust. We present a case series of our first 4 months data.

Method

All TULA cases (n = 39) performed between Aug-Dec 2020 were included. Data was gathered prospectively including patient demographics, co-morbidities, initial cancer diagnosis and number of subsequent recurrences, post-procedural complications, and patient procedural satisfaction.

Results

Median age was 82 years (range 34-96) and median number of co-morbidities were 4 (range 0-10). Previous bladder cancer diagnosis was present for 85% with the most common initial stage G2pTa (n = 11). Median number of recurrences was 1 (range 1-5). Median patient perceived pain score was 3 (range 1-7) with 100% of patients preferring TULA over TURBT. Reasons included reduced procedural time (n = 18) and enhanced recovery (n = 15). Only 1 patient was readmitted post-procedure due to haematuria, however urine was clear after catheterisation and the patient was discharged.

Conclusions

TULA is safe for all low risk NMIBC, particularly for frail patients. It is well tolerated and facilitates improved patient experience. It also alleviates demand on theatre capacity and inpatient beds which has a positive effect on surgical waiting lists. Further audit of clinical outcomes should continue as recommended by NICE.

1234 Emergency Urology Procedures During COVID-19 Pandemic: A 2 Monthly Prospective Study

Introduction

COVID-19 resulted in Regional tiered restrictions being introduced across the UK with subsequent implications for planned and emergency care. Specific to Merseyside Tier 4 and Tier 2 restrictions were introduced in late 2020. At the onset of the pandemic in the Spring, elective work ceased, and emergency admissions were minimal. The purpose of this study was to examine the volume and nature of all emergency admissions to a Urology unit in Merseyside in the 2nd wave of the pandemic during two different tiers of national restrictions.

Method

A prospective audit examining all emergency urological activity was conducted in Whiston Hospital from October 2020 when the Tier 4 restrictions were introduced to Tier 2 was introduced. Data was obtained by identifying patients using the electronic theatre listing system.

Results

A total of 52 emergency cases were performed (24 in November Tier 4, 28 in December Tier 2). A total of 12 different procedures were performed. The commonest procedure performed was stent insertion (26), followed by scrotal exploration (7). One patient required transfer to a different hospital. In total 4 calls were made by general surgery and 2 by gynaecology for urological assistance in theatre. Two urology patients returned to theatre. Direct Consultant involvement occurred in 19 cases (37%).

Conclusions

Unlike the Spring lockdown acute urology operations presented despite regional restrictions. A total of 52 cases were performed with more occurring in Tier 2. Stent insertion was the commonest procedure with the majority of the cases performed by registrars.

Lifestyle Habits and Wellbeing Among Physicians in Pakistan: A Cross-Sectional Study

Introduction Physicians' attitude towards a healthy lifestyle is important as it determines their extent of acceptance of these habits leading to overall well-being. Physicians with healthy lifestyle habits are more confident in advocating the same to their patients and their patients are keener in adopting lifestyle modifications. This study aimed to evaluate the lifestyle habits, wellbeing, and mental health of physicians in Pakistan. Methods A multi-center, cross-sectional survey was conducted with physicians across Pakistan from August to October 2020. A total of 1406 participants were gathered by the non-probability convenient sampling technique. Data were collected physically from the participants. A semi-structured, self-administered questionnaire comprising socio-demographic information, lifestyle habits, mental well-being, and well-being, in general, was filled. Mental wellbeing was assessed using the Warwick Edinburg Mental Wellbeing Scale (WEMWBS) comprising 14-positive items scored on a 1-5 point Likert scale where 1 corresponds to "none of the time" and 5 corresponds to "all of the time." The score ranges from a minimum of 14 to a maximum of 70 points. Higher scores are associated with higher levels of mental wellbeing. Data were stored and analyzed using IBM-SPSS v.23 (IBM Corp., Armonk, NY). Results In this survey, there were 1284 (91.3%) males and 122 (8.7%) females with a mean age of 44.09 ± 11.18 years. More than half (n=768; 53.0%) of the physicians reported their general health as "good," 1045 (73%) were satisfied with their work-life balance, 206 (14%) had seen a physician for their health in the last six months, and 358 (25%) never had a routine medical checkup. When WEMWBS was applied, participants ≤40 years scored significantly higher than the older age group (p<0.01). Male physicians also scored significantly higher on WEMWBS (52.35 ± 8.78) as compared to their female counterparts (p<0.01). WEMWBS scores also varied significantly across various levels of expertise - with consultants scoring the highest (52.67 ± 9.02) and others scoring the lowest (48.63 ± 8.58; p=0.02). Physicians practicing in the public hospitals only (53.05 ± 9.02), scored higher on WEMWBS as compared to those in the private hospitals (51.28 ± 8.12) as well as those practicing in private clinics only (49.57 ± 8.82; p<0.01). Physicians who perceived their health as excellent scored highest on WEMWBS (53.55 ± 9.31), than those who considered their health good (51.68 ± 8.40), poor (50.71 ± 9.27), or fair (48.70 ± 8.15; p<0.01). The correlation analysis showed a significant negative correlation of WEMWBS scores with health in general (2.5% variation) and age (0.92% variation; p<0.01). Conclusion Physicians in our study were mostly satisfied with their general health and work-life balance. Nevertheless, their mental health well-being was not satisfactory, as assessed by WEMWBS. There is a dire need for lifestyle modifications among the medical practitioners who may improve their mental and physical well-being subsequently allowing them to cater to their patients more effectively. It is recommended that physician-patient-specific interventions should be developed to target the health status and mental well-being of a physician and to encourage the physicians especially the fresh medical graduates and young doctors to indulge in healthy activities.

845 Flattening the Learning Curve: The Evaluation of Extended Laparoscopic Simulation Training for Novice Surgeons

Introduction

Associated with faster postoperative recovery, reduced length of hospital stays and scarring; laparoscopy has become the favoured approach for many surgical procedures across a range of specialties. However, due to its challenging learning curve, it has also been associated with increased theatre time and higher complication rates.

Method

A prospective, observational study with box trainers was carried out by novice medical students and trainees to evaluate the efficacy of long duration courses on skill acquisition. The novice group undertook a 5-week curriculum composed of lectures, demonstrations and spaced timed-assessments involving 3 tasks: hoop placement, stacking of sugar cubes and surgical cutting.

Results

Time taken for novice participants to complete a task individually and collectively improved markedly from the first to the third attempt, with an overall 44% reduction in time observed over the 5-weeks. We invited back 6 novice participants and 6 core surgical trainees after 4-weeks to complete the same tests. There was a further 18% time improvement in the novice group, with 44% faster task completion.

Conclusions

Given the success of this study and other simulation courses reported in the literature, we recommend more courses adopt a spaced-out approach; and a simulation curriculum for surgical trainees to cultivate greater skill acquisition.

A case report of coexistence of ectopic lingual thyroid with hypoplastic normal thyroid gland

Ectopic lingual thyroid along with a normally located thyroid gland is an uncommon condition caused by an aberrant descent of thyroid during embryogenesis. It is more common among females and expresses during puberty, pregnancy and menopause. It is mostly associated with hypothyroidism. Patient usually presents with complaints of dysphagia, dysphonia and suffocation. Treatment of choice depends upon the primary complaint of the patient. We present the case of a young female who underwent tracheostomy to relieve respiratory tract obstruction during puberty and was later diagnosed as a case of ectopic lingual thyroid by radioactive iodine uptake and CT scan imaging. She had an associated hypothyroidism; patient was then put on thyroxine and after making her euthyroid she was operated by transoral route and her ectopic lingual thyroid was removed. She was discharged on a maintenance dose of thyroxin.

Synergic effects of cancer stem cells markers, CD44 and embryonic stem cell transcription factor Nanog, on bladder cancer prognosis

Background: Therapy that targets cancer stem cells has the potential to eradicate cancer and prevent tumour recurrence. Therefore, we hypothesized the combined prognostic significance of stem cell markers CD44 (prevalent in basal layer of urothelial carcinoma) and Nanog (embryonic stem cell transcription factor) in bladder cancer.Material and Methods: CD44 and Nanog expression were determined by immunohistochemistry in 112 bladder cancer cases of which 79 were non-muscle invasive and 33 muscle invasive.Results: A significant correlation was found between CD44 and Nanog expression (r = 0.41, p < 0.001). The bladder cancer patients with high CD44 and Nanog expression had poor recurrence-free survival and poor overall survival (all p < 0.01). Multivariate Cox regression analysis identified lymph node positivity (hazard ratio; HR 3.81, 95% confidence interval; CI 1.66-8.75), CD44 (HR/95%CI 7.03 [3.04-16.22]) and Nanog (HR/95%CI 2.89 [1.23-6.77]) as independent prognostic biomarkers for recurrence-free survival, whilst a combined index of CD44 and Nanog expression (high expression group; HR/95%CI 25.45 [6.71-96.50] for recurrence-free survival) and lymph node positivity (HR/95%CI 3.68 [1.63-8.33] for recurrence-free survival) were independent prognostic biomarkers for recurrence-free survival and overall survival (all p < 0.001).Conclusions: A combined index of CD44 and Nanog expression is a promising prognostic predictor of recurrence-free survival and overall survival in bladder cancer. It may help identification of patients who will benefit from intensive treatment.

Leveraging Electronic Dental Record Data to Classify Patients Based on Their Smoking Intensity

Background Smoking is an established risk factor for oral diseases and, therefore, dental clinicians routinely assess and record their patients' detailed smoking status. Researchers have successfully extracted smoking history from electronic health records (EHRs) using text mining methods. However, they could not retrieve patients' smoking intensity due to its limited availability in the EHR. The presence of detailed smoking information in the electronic dental record (EDR) often under a separate section allows retrieving this information with less preprocessing.

Objective To determine patients' detailed smoking status based on smoking intensity from the EDR.

Methods First, the authors created a reference standard of 3,296 unique patients’ smoking histories from the EDR that classified patients based on their smoking intensity. Next, they trained three machine learning classifiers (support vector machine, random forest, and naïve Bayes) using the training set (2,176) and evaluated performances on test set (1,120) using precision (P), recall (R), and F-measure (F). Finally, they applied the best classifier to classify smoking status from an additional 3,114 patients’ smoking histories.

Results Support vector machine performed best to classify patients into smokers, nonsmokers, and unknowns (P, R, F: 98%); intermittent smoker (P: 95%, R: 98%, F: 96%); past smoker (P, R, F: 89%); light smoker (P, R, F: 87%); smokers with unknown intensity (P: 76%, R: 86%, F: 81%), and intermediate smoker (P: 90%, R: 88%, F: 89%). It performed moderately to differentiate heavy smokers (P: 90%, R: 44%, F: 60%). EDR could be a valuable source for obtaining patients’ detailed smoking information.

Conclusion EDR data could serve as a valuable source for obtaining patients' detailed smoking information based on their smoking intensity that may not be readily available in the EHR.

Population-based cohort study of variation in the use of emergency cholecystectomy for benign gallbladder diseases

Background

The aims of this prospective population-based cohort study were to identify the patient and hospital characteristics associated with emergency cholecystectomy, and the influences of these in determining variations between hospitals.

Methods

Data were collected for consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing the performance of emergency cholecystectomy were analysed by means of multilevel, multivariable logistic regression modelling using a two-level hierarchical structure with patients (level 1) nested within hospitals (level 2).

Results

Data were collected on 4744 cholecystectomies from 165 hospitals. Increasing age, lower ASA fitness grade, biliary colic, the need for further imaging (magnetic retrograde cholangiopancreatography), endoscopic interventions (endoscopic retrograde cholangiopancreatography) and admission to a non-biliary centre significantly reduced the likelihood of an emergency cholecystectomy being performed. The multilevel model was used to calculate the probability of receiving an emergency cholecystectomy for a woman aged 40 years or over with an ASA grade of I or II and a BMI of at least 25·0 kg/m2, who presented with acute cholecystitis with an ultrasound scan showing a thick-walled gallbladder and a normal common bile duct. The mean predicted probability of receiving an emergency cholecystectomy was 0·52 (95 per cent c.i. 0·45 to 0·57). The predicted probabilities ranged from 0·02 to 0·95 across the 165 hospitals, demonstrating significant variation between hospitals.

Conclusion

Patients with similar characteristics presenting to different hospitals with acute gallbladder pathology do not receive comparable care.

Road rage and road traffic accidents among commercial vehicle drivers in Lahore, Pakistan

Road rage and road traffic accidents increase the burden of morbidity and mortality in a population. A cross-sectional survey with convenience sampling was conducted among commercial vehicle drivers in Lahore, Pakistan (n = 901) to record their behaviours/experiences regarding road rage and road traffic accidents. Respondents were asked about incidents of shouting/cursing/rude gestures or threats to physically hurt the person/vehicle, by others or themselves, in the previous 24 hours or 3 months, and their involvement in road traffic accidents in the previous 12 months. Auto-rickshaw drivers were significantly more likely to report various road rage experiences/behaviours and involvement in accidents compared with bus and wagon drivers. A total of 112 respondents (12.4%) reported being involved in a road traffic accident in the previous 12 months but traffic police did not record the accident in 52.7% of cases. The results of this study underline the need to improve road safety in Pakistan.

Road rage behaviour and experiences of rickshaw drivers in Rawalpindi, Pakistan

A cross-sectional survey with convenience sampling was conducted among rickshaw drivers in Rawalpindi, Pakistan to study their road rage behaviour and experiences. Cumulatively 318 male drivers participated in this study. The most common forms of road rage reported were: having been shouted at; and having experienced rude gestures from other drivers (78.9% each). Least common forms of road rage reported were: threats of physical hurt or having actually been physically hurt ( < or = 3% each). Rickshaw drivers with shorter driving time (< or = 10 years) had significantly more road rage experiences than those who had been driving for more than 10 years (P < 0.01). There is a need for nationally representative surveys to study road age in commercial vehicle drivers so as to improve road safety in Pakistan.

Trapidil inhibits monocyte chemoattractant protein-1 and macrophage accumulation after balloon arterial injury in rabbits

Trapidil (triazolopyrimidine) is an antiplatelet agent that acts in part as a phosphodiesterase inhibitor and as a competitive inhibitor of the platelet-derived growth factor (PDGF) receptor. Trapidil has been shown to attenuate intimal hyperplasia in rat and hamster models of balloon arterial injury and to inhibit restenosis after percutaneous transluminal coronary angioplasty in several small clinical trials. Monocyte chemoattractant protein-1 (MCP-1) is a PDGF-inducible monocyte chemoattractant that is thought to play a particularly important role in recruiting monocyte/macrophages to sites of atherosclerosis and vessel injury. We hypothesized that, because of its ability to antagonize PDGF-mediated events, trapidil would inhibit the synthesis of MCP-1 and decrease macrophage accumulation in the injured arterial wall. Hypercholesterolemic rabbits were treated with trapidil (60 mg/kg/day subcutaneously) the day before and then daily for 6 days after balloon injury of the femoral artery; control rabbits received vehicle only. Trapidil resulted in a 75% reduction in MCP-1 expression and macrophage accumulation in the arterial wall 7 days after injury. This study suggests that trapidil has potent anti-inflammatory properties and that its activity in attenuating intimal hyperplasia may be in part attributed to its effects on macrophage accumulation.

Improved immunotherapy for pulmonary tuberculosis with Mycobacterium vaccae

We previously demonstrated that a single intradermal injection of 10(9) irradiation-killed M. vaccae, given 1 month after starting chemotherapy, caused significant changes in responses to mycobacterial antigens. Amongst 38 patients with pulmonary tuberculosis, 29% had lymphocytes responding to common myocobacterial antigens after the injection, compared with only 11% of 49 similar patients after an injection of saline (p less than 0.03). To increase the proportion of responders to these antigens, six modifications of the potentially immunotherapeutic injection, randomized with injections of saline, have been assessed by biochemical, clinical, haematological, immunological and radiological criteria. Subsequent lymphocyte proliferation to mycobacterial antigens enabled the modifications to be ranked in order of efficacy. Tuberculin plus murabutide plus 10(9) irradiated M. vaccae (36% of 25), an autoclaved preparation of 10(9) M. vaccae (45% of 22), and 2 x 10(9) irradiated M. vaccae (75% of 12) were the most effective. Antibody responses in several IgG subclasses to mycobacteria, but not streptococci, were also significantly increased by the most effective modifications over the 8 weeks following injection. Detailed radiological study showed that use of the autoclaved bacilli was followed by a delay in clearing of consolidation, but by better closing of cavities than was found in the control group, suggesting enhanced, or altered, immunological activity around the lesions.

An investigation of patients with pulmonary tuberculosis in Kuwait in preparation for studies of immunotherapy with Mycobacterium vaccae

Sixty-five patients, many of them immigrant to Kuwait, with bacteriologically proven, adult type, pulmonary tuberculosis were studied by many parameters over the 4 months following diagnosis. Twelve were infected with tubercle bacilli resistant to at least one anti-tuberculosis drug. Preliminary evidence suggested that this was frequently primary resistance in patients infected in their countries of origin. The Kuwaiti environment results in very high skin test and lymphocyte proliferative responses (LTT) to shared and species specific antigens of mycobacteria in healthy persons. In comparison, patients with tuberculosis lacked cellular responses to group i and group ii antigens, but had increased IgG and IgA binding to mycobacterial antigens in general. LTT responses to added interleukin 2, and production of alpha interferon, were normal in our patients, but induction of gamma interferon in response to phytohaemagglutinin was reduced initially, rising towards normal during treatment. Biochemical and haematological abnormalities present at the time of diagnosis rapidly corrected. The disease differed from that reported in most previous studies in that fever was uncommon, the disease was never fatal, and most tuberculin tests were not necrotising. This implied that a detrimental immunopathological component is less pronounced in those exposed to the Kuwaiti environment, and a hypothesis is put forward to explain this.

Immunotherapy with Mycobacterium vaccae as an adjunct to chemotherapy in the treatment of pulmonary tuberculosis

47 patients with adult-type pulmonary tuberculosis attending the Chest Diseases Hospital in Kuwait were given a single injection of 10(9) irradiation-killed M. vaccae after 1 month of a 9-month course of chemotherapy. The patients were followed-up for 3 more months in double blind comparison with 65 patients given an injection of saline (placebo). The immunotherapeutic injection produced a small local lesion in 44/47 patients, 18 of which ulcerated and produced small scars. Immunotherapy made no measurable difference to the bacteriological, biochemical, haematological, or radiological parameters measured. However it was associated with significantly improved weight gain, reduced size of skin test response to Tuberculin, increased lymphocyte proliferation to common mycobacterial antigens, and increased antibody levels to mycobacterial antigens. The changes in skin test and LTT responses were related and occurred in 29% of patients whose recognition of common mycobacterial antigens returned to normal. The remaining patients did not differ in these respects from those receiving placebo. The proportion of patients whose responses were improved was very similar to that achieved using the same immunotherapeutic agent in a group of treated multibacillary leprosy patients.

Penetrating chest trauma: a review of 150 cases

Penetrating injuries of the chest with emphasis on the policy of selective management in 150 cases, 145 males and 5 females, with age ranging from 5-60 years were reviewed. Chest pain and breathlessness were the commonest presenting features. Haemorrhagic shock and haemoptysis were noted in 30% and 20% cases respectively. Fire arms injury was the leading cause of chest trauma, being present in 80 (53.33%) cases. Except for 6 (3 cases had superficial stab wounds and 3 died on way to operation theatre), all patients (144) needed surgical intervention (tube thoracostomy drainage in 110 and major operation in 34 patients). There were 7 deaths in this study; massive haemorrhage was the cause of death in 4 and septic shock in 3 cases. An overall success rate of 95.34% was observed in this series.

HLA-DR and tuberculin tests in rheumatoid arthritis and tuberculosis

Responses to four new tuberculins were found to be significantly reduced in 46 patients with rheumatoid arthritis in comparison with a control group of 79. Except for tuberculin itself, the same was found in 111 patients with tuberculosis. In common with patients with tuberculosis and leprosy, those with rheumatoid arthritis did not respond to common mycobacterial (group i) antigen. Three DR haplotypes were found to have significant effects on skin test responsiveness of the rheumatoid patients but had little or no effect on that of the patients with tuberculosis and none on that of the healthy control group. Rheumatoid patients with the HLA-DR4 haplotype had significantly greater responses to all four reagents than did non-DR4 patients, but their responses to leprosin A and scrofulin remained significantly lower than those of the control group. Possession of HLA-DR3 haplotype was associated with skin test positivity approaching normal, but the sizes of responses were reduced. Possession of DR7 was associated with an unexpected reduction in skin test positivity, especially in the case of tuberculin. These results support the hypothesis that mycobacteria, or autoantigens cross reactive with mycobacteria, may be involved in the aetiology of rheumatoid arthritis. The results also show that the regulation and specificity of responsiveness to mycobacterial antigens are different in patients with rheumatoid arthritis with different HLA-DR haplotypes.

Unexpected findings amongst the skin test responses to mycobacteria of BCG vaccinated Kuwaiti school children

A multiple skin test survey was carried out in Kuwait on 1200 school children aged 8-11 years, and on 1228 children aged 12-16 years. With only 15 exceptions, all these children had received vaccination with Japanese BCG just before they started school, 5 years and 9 years earlier respectively. Tuberculin positivity was almost 90% in both groups, with a mean response size of 8.7 mm. This was associated with remarkably high responsiveness to many of the other mycobacterial species investigated. Since this high reactivity was also to Mycobacterium ulcerans, a species most unlikely to be present in Kuwait, it is proposed that this might be due to responsiveness to group ii antigen which is present in all slow growing species. Only M. flavescens and M. rhodesiae amongst the fast growing species, were absent as sensitising organisms. After correction for the supposed reactivity to group ii antigen, M. avium B, M. gordonae, M. ulcerans and M. xenopi amongst the slow growing species, also appeared to be absent from the Kuwait environment. The species most commonly encountered were M. leprae, M. chitae, M. neoaurum, M. diernhoferi, and M. vaccae in this order. This was a remarkable finding for a country assumed to be poor in contact with environmental species, and known to have a very low prevalence of leprosy. As previously reported from Iran, but not confirmed in other places, there was a 95% correlation between responsiveness to Leprosin A and Vaccin. Amongst the slow growing species M. avium A, M. intracellulare, and M. kansasii appear to be frequent sensitising agents, in common with many other places.