Ulcerative colitis associated with aplastic anemia; a case report

Anemia is the most common hematologic disorder in patients with ulcer-ative colitis [UC]. In some cases, normochromic anemia results from the presence of chronic disease; however blood loss or malabsorption may lead to an iron deficiency anemia with hypochromic appearance. Other rare hematologic manifestations associated with UC include myelodysplastic syndromes and leukemia. Several investigators have suggested a clinical association between inflammatory bowel disease and myelodysplastic syndrome, which may they share an immune dysfunction and impairment of T-lymphocytes activities. UC is an inflammatory bowel disease of unknown etiology that mainly affects the mucosa of the colon. Immune mechanisms play an important role in UC, and immunogenetic factors have been implicated in the development of the disease. Aplastic anemia is a bone marrow stem cell disorder characterized by ineffective hematopoiesis, leading to pancytopenia. Although aplastic anemia is frequently idiopathic, the immune-mediated suppression of hematopoiesis may be implicated in at least half of patients, since more than half of these patients achieve hematological remission in response to immunosuppressive therapy. We report here a rare case of UC associated with pancytopenia requiring a blood transfusion in which a bone marrow examination showed aplastic anemia. A common pathogenic link between UC and aplastic anemia is suggested in this patient on the basis of the shared immunologic impairment underlying both diseases

Increased expression of HLA DR2 in acquired aplastic anemia and its impact on response to immunosuppressive therapy

To study the frequency of HLA DR2 status of patients with aplastic anemia and their response to immunosuppressive therapy at a tertiary care hospital. Thirty eight consecutive patients of acquired aplastic anemia were evaluated with respect to demographic features, severity of HLA DR2 status and response outcome to immunosuppressive therapy. The mean age of the patients was 24.6 years + 16.4 with a male to female ratio of 2.8:1. Positivity of HLA DR2 was markedly high in acquired aplastic anemia patients. Twenty four [65%] out of 38 patients as compared to 45 [15%] of 300 healthy controls [p<0.0001] were positive for HLA DR2. Response to immunosuppressive therapy, which included antilymphocyte globulin, cyclosporin and methylprednisolone, was available in sixteen HLA DR2 positive patients and was found satisfactory in 12/16 [75%] patients. HLA DR2 was significantly higher in patients with acquired aplastic anemia and favourable response to immunosuppressive therapy was also associated with HLA DR2 positivity

Estudios genéticos y ambientales en el lupus eritematoso sistémico / Genetic and environmental studies in systemic lupus erythematosus

The cause of systemic lupus erythematosus (SLE) remains rather poorly understood. Accumulating reported evidence suggests that both environmental and genetic factors play a part. They somehow create an abnormal CD4 T-cell driving force which results in autoantibody production. We present a synthesis of previously published study. The objective of our original study was to examine the role of genetic and environmental factors in 26 families having two or more members of SLE. The role of genetic factors was examined by determining the HLA of each individual in the study. No association between SLE and HLA-A, B, C antigens was found. There was however, a significant association with HLA-DR2 in white subjects with SLE. The most striking finding was that HLA sharing was increased among the affected members, suggesting genetic similarities. Seven of 14 sib pairs (50%) who had concordant SLE were HLA identical as opposed to an expected 25%. The role of environmental factors was examined by determining lymphocytotoxic antibodies (LCA) in patients and their consanguineous and non-consanguineous relatives. Interestingly 15/18 (83%) patients with SLE and 11/22 (50%) consanguineous relatives had LCA, while 1/9 (11%) spouses and 2/42 (5%) healthy controls had these antibodies. We conclude that genetic factors have a role in the development and expression of SLE. Environmental factors may trigger the disease in genetically susceptible individuals.

La causa del lupus eritematoso sistémico (LES) continúa con deficiente comprensión hasta el momento actual. Abundan los datos publicados en el sentido de que tanto los factores ambientales como los genéticos cumplen cierta función en su desarrollo. De algún modo actúan induciendo la producción de células T tipo CD4 anormales, responsables a su vez de la producción de un autoanticuerpo. Presentamos la síntesis de un estudio que hemos publicado recientemente. El objetivo de nuestra investigación original fue examinar el papel de los factores genéticos y ambientales en 26 familias con dos o más miembros enfermos de LES. La participación del componente genético fue analizada a través de la determinación del HLA de cada individuo incluido en el estudio. No se encontró relación alguna entre LES y los antígenos HLA-A, B, C. Sin embargo, hubo una asociación significativa con HLA-DR2 en individuos de raza blanca con esta enfermedad del tejido conectivo. El hallazgo más notorio fue que la participación del HLA era mayor entre los miembros afectados, señal de la existencia de similitudes genéticas. Siete de 14 pares de allegados consanguíneos (50%) que poseían LES concordante eran HLA idénticos, a diferencia del 25% que en realidad se esperaba. El papel de los factores ambientales se analizó determinando los anticuerpos antilinfocitotóxicos (ALT) en los pacientes y en sus familiares consanguíneos y no consanguíneos. En forma llamativa, 15 de 18 individuos con LES (83%) y 11 de 22 familiares consanguíneos (50%) tenían ALT, mientras que sólo 1 de 9 cónyuges (11%) y 2 de 42 controles sanos (5%) eran portadores de estos anticuerpos. Concluimos que los factores genéticos desempeñan un papel en el desarrollo y la expresión del LES. Los factores ambientales pueden actuar como desencadenantes de la enfermedad en individuos genéticamente susceptibles.

The Frequency of HLA Alleles in Korean Children with Aplastic Anemia and the Correlation with the Response to Immunosuppressive Treatment / 대한소아혈액종양학회지

PURPOSE: Immune pathophysiology of aplastic anemia (AA) has been indirectly inferred from responses to immunosuppressive agents. An association between AA and HLA-A2, or HLA-DR2 (its serologic split, HLA-DR15; or its molecular correspondents, DRB1*1501) has been implicated. The presence of HLA-DR15 (including DR2 or DRB1*15) has been closely associated with a favorable response to immunosuppression in AA. This study was aimed to characterize Korean patients with AA by determining the association with certain HLA alleles, such as HLA-DR2 or HLA-A2, and their implications in terms of the response to immunosuppression. METHODS: One-hundred eighteen children with AA from 10 university hospitals between 1990 and 2001 were enrolled in this multicenter, retrospective study. Among them, HLA data were available from 80 patients. Tests of proportions were used to compare allelic frequencies. RESULTS: The frequency of HLA-A2 (58.8%) or HLA-DR2 (24.7%) in AA was not significantly different from those of the controls. Analysis of the patients treated with immunosuppression (N=86) showed that, 50.0% of patients showed a response, including 16.0% of complete response at 6 months. The presence of DR2 allele did not portend a favorable response to immunosuppressive therapy. CONCLUSION: Unlike Western countries, the association of AA with certain HLA alleles was not documented in the Korean population. Moreover, the presence of HLA-DR2 did not predict a favorable response to immunosuppression. This peculiar characteristics of Korean AA needs to be investigated whether these findings reflect ethnic differences, different contribution of immune-mediated AA, different immune mechanisms, or mere limitation by number of study patients.

HLA-DR Polymorphism in Hepatitis B Virus-associated Glomerulonephritis / 대한신장학회잡지

BACKGROUND: Hepatitis B virus (HBV)-associated glomerulonephritis (HBGN) occurs with high prevalence in Asia, and accounts for over 30% of secondary glomerulonephritis in Korea. However, the association between HLA and HBGN has been hardly reported upon in the literature. METHODS: A total of 50 Korean patients with HBGN, 100 HBsAg (-) healthy controls and 89 HBsAg (+) controls (subjects with chronic HBV infection, HBsAg positive at least for 6 months) were included. HLA-DR typing was done using a reverse sequence specific oligonucleotide typing kit and HLA-DRB1 genotyping was done for HLA-DR2 positive samples by PCR-single strand conformational polymorphism method. RESULTS: In the HBGN patients, HLA-DR2 was highly significantly increased compared with HBsAg (-) controls (p=0.0002, corrected p=0.002, OR=4.0) and also compared with HBsAg (+) controls (p= 0.0005, corrected p=0.006, OR=3.7). Different HLA- DR2 alleles were strongly associated with different pathologic subtypes of HBGN: DRB1*1502 was associated with membranoproliferative glomerulonephritis (MPGN) (p=0.0003, corrected p=0.004, OR=14.5), and DRB1*1501 with membranous nephropathy (MN) (p= 0.05, OR=3.8). These associations were also found to be significant compared with HBsAg (+) controls (HBV-MPGN, p=0.002; HBV-MN, p=0.04). DR13 was found to have some protective effect in HBV infection (p=0.01, OR=0.3) and DR11 was found to be weakly associated with HBV infection (p=0.01, OR= 4.6), however these HLA alleles were not associated with disease susceptibility to HBGN. CONCLUSION: These results suggest that HLA- DR2 or a closely associated genetic factor is associated with disease susceptibility to HBGN, and different HLA-DR2 subtypes are associated with different pathologic subtypes of HBGN in Koreans.

Analysis of human leukocyte antigens class II-DR in Brazilian children and adolescents with systemic lupus erythematosus

OBJECTIVE: To analyze the frequency of human leukocyte antigens class II-DR in children and adolescents with systemic lupus erythematosus. PATIENTS AND METHODS: Fifty-fiveBrazilian systemic lupus erythematosus children and adolescents and 308 healthy individuals were studied. Gender, race, and age of onset of systemic lupus erythematosus were recorded. The human leukocyte antigens typing of class II-DR was carried out by polymerase chain reaction amplification with sequence-specific primers (PCR-SSP). Data were analyzed statistically using the chi square test with Yates' correction, Fisher's exact test, and Bonferroni's correction. RESULTS: Human leukocyte antigen-DR 15 was the most frequently detected antigen in this group of children and adolescents, and it also occurred more frequently in the female group, in children with onset of systemic lupus erythematosus between 0 and 9 years and between 10 to 14 years, and in the Black race group, but these associations were not statistically significants. CONCLUSION: In this group of children and adolescents with a high degree of racial admixture, we could not verify a significant association between human leukocyte antigens class II-DR and systemic lupus erythematosus

HLA-DR2 subtypes & immune responses in pulmonary tuberculosis.

BACKGROUND & OBJECTIVES: HLA-DR2 has been shown to be associated with the susceptibility to pulmonary tuberculosis and altered antibody and lymphocyte response in pulmonary tuberculosis. In the present study, the influence of DR2 subtypes on antibody titre and lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens (10 micrograms/ml) was studied in 22 patients with active pulmonary TB (ATB), 50 inactive (cured) TB (ITB) patients and 36 healthy control subjects. METHODS: HLA-DR2 gene was amplified by polymerase chain reaction (PCR) and dot-blotted. Genotyping of DRB1*1501, *1502, *1503, *1601 and *1602 was carried out using sequence specific oligonucleotide probes (SSOPs) and detected by chemiluminescence method. Antibody titre as well as lymphocyte response to M. tuberculosis antigens were measured by enzyme linked immunosorbent assay (ELISA) and lymphocyte transformation test (LTT) respectively. RESULTS: The allele frequency of DRB1*1501 was significantly increased in pulmonary tuberculosis patients as compared to controls (P < 0.05). No marked difference in the antibody titre and lymphocyte response to M. tuberculosis antigens was observed between the DRB1 *1501, *1502 and *1503 positive or negative controls, ATB and ITB patients. DRB1 *1501 and *1502 positive as well as negative ATB patients showed a higher antibody titre as compared to controls and ITB patients. ITB patients with *1502 showed a higher lymphocyte response as compared to *1502 positive controls (P < 0.001) and ATB patients (P < 0.05). Similarly, an increased lymphocyte response was observed in *1501, and *1503 negative ITB patients compared to *1501 and *1503 negative controls and ATB patients. INTERPRETATION & CONCLUSION: The present study revealed that DRB1 *1501 may be associated either alone or with other DR2 alleles, with the susceptibility to pulmonary tuberculosis. None of the DR2 alleles influenced the antibody and lymphocyte response to M. tuberculosis culture filtrate antigens. This suggested that HLA-DR2 gene/gene products as a whole may influence the immune response in pulmonary tuberculosis.

Human leucocyte antigen [HLA] class one [A1, B7] and class two [DR-11] are new factors affecting the incidence of colonic carcinoma

The problem of colonic carcinoma is still a dilemma regarding, diagnostic and therapeutic strategy. Many factors have been found to affect the incidence of this type of cancer such as age, sex, diet and previous abdominal surgery. A survey study revealed that in normal [control] population HLA-A1 was positive in about 50%. HLA-B7 was positive in about 8% and HLA-DR11 was positive in about 40%. The aim of this study was to find a relation between the above-mentioned types of HLA and the increased or decreased risk of incidence of colonic carcinoma. Thirty patients were diagnosed after using: careful history taking, clinical examination, laboratory, and radiological investigations. Finally colonoscopy and biopsy were done. Detection of [HLA- A1. B7] was done serologically using Sigma USA. Detection of [HLA-DR 11] was done using lymphobeads method [Biotest Great Britain [UK] Itd]. HLA-A1 was found to be positive in eight patients while HLA-B7 was positive in seven patients, and HLA-DR 11 was positive in ten patients. HLA-A1 positive results were associated with increased risk of incidence of colonic carcinoma by 45%, while HLA-B7 positive results were associated with increased risk of incidence by 233% and presence of HLA-DR11 positive results were associated with decreased risk incidence by 80%. So we can consider the above-mentioned HLA types as new factors affecting the incidence of colonic carcinoma

A Case of Narcolepsy after Traumatic Brain Injury / 신경정신의학

The authors reported a case and its diagnostic process of post-traumatic narcolepsy which had developed after a head trauma. The 51-years-old patient showed frequent generalized paralytic attack, which was aggravated during stressful situation, diet time, and in front of hospital staffs. During the paralytic attack, consciousness was alert, and he never collapsed to hurt. All laboratory findings including serum potassium level were within normal limit, and also brain imaging studies and electroencephalography revealed no specific abnormal findings. Our clinical impression was a conversion disorder or a malingering at first, but after the detailed history taking and the careful observation, daytime sleep attack and some sleep problems were revealed. Thus nocturnal polysomnography and multiple sleep latency test(MSLT) were performed, and then the authors could diagnose as "narcolepsy". HLA-DR2 typing was negative. After imipramine trial, the frequency and the intensity of attack was dramatically reduced. The authors concluded that narcolepsy should be considered in the differential diagnosis of sleepiness or transient loss of muscle tone after traumatic brain injury.

Permanent neonatal diabetes mellitus: epidemiology, mode of presentation, pathogenesis and growth.

Permanent neonatal diabetes mellitus (PNIDDM) is a rare form of IDDM with unclear etiology and pathogenesis. We determined the incidence and prevalence rates and studied the clinical and biochemical features of PNIDDM in the Sultanate of Oman. The mean incidence rate during the study period from January 1989 to December 1994 was 1.788 +/- 0.82 per 100,000 live births per year. At the end of December 1994 the prevalence rate was 2.4 per 100,000 children below the age of 5 years. They constituted 41.6% of all cases of IDDM in this age group. Diarrhoea, fever, lethargy, poor feeding and failure to thrive were the most common presenting symptoms. Dehydration and tachypnoea were the most common signs. All patients who developed IDDM during the neonatal period had intrauterine growth retardation and 4.5 presented with diabetic ketoacidosis (plasma glucose 37 +/- 9 mmol/L, pH 7.12 +/- 0.1). Hypertriglyceridemia was a constant feature (19.4 +/- 4.8 mmol/L). They were products of consanguineous marriage with significantly high prevalence of IDDM and NIDDM in their family members. None of the infants had clinical or immunological evidence of congenital viral infection. Three of the five children had HLA-DR2, the diabetes resistance alleles. C-peptide secretion was absent during and after metabolic control of hyperglycemia in all the studied infants and none had circulating islet cell antibody at presentation or during the first year after diagnosis. Despite marked growth retardation at birth, there was a significant improvement of growth after initiating insulin therapy. Four of the 5 patients had normal developmental milestones, one had mild developmental delay following a severe and prolonged attack of hypoglycemia. None of the patients had exocrine pancreatic deficiency. In summary, the very high rate of parental consanguinity, occurrence in both sexes and in two siblings in the same family, absence of islet cell antibodies and the presence of HLA-DR2 loci in 3/5 of patients suggest that PNIDDM is a different disease process to standard IDDM in childhood and an autosomal recessive mode of transmission.

Response to Immunosuppressive Therapy and an HLA-DR Allele in Children with Aplastic Anemia / 대한혈액학회지

BACKGROUND: Genetic susceptibility to a variety of disease has been shown and it has recently been suggested that aplastic anemia is more common in adults who are HLA-DR2+ than in the general population. METHODS: To investigate whether certain HLA-DR gene is more common in children with aplastic anemia and HLA-DR2+ gene is associated with susceptibility to cyclosporine A (CyA), we analyzed the results of HLA-DR typing in 37 children with aplastic anemia with sequence specific oligonucleotide probe (SSOP) method. RESULTS: Eight patients were DR2+, and there was no more common than the normal population. All of the 8 patients with DR2+ were DRB1*1501+ with high resolution HLA typing. Of the 8 patients with DRB1*1501+, 3 patients were treated with CyA alone (2 patients) or CyA plus ATG (1 patient), 2 patients were treated with ATG (1 patient) or ALG alone (1 patient). Patients treated with CyA only or CyA plus ATG had either a complete (1 patient) or partial (2 patients) response and patients treated ATG or ALG alone had no response. CONCLUSION: Although incidence of HLA-DR2 was not significantly higher in children with aplastic anemia then normal population, response rate to CyA was significantly high in the DR2+ patients.

Histocompatibility antigens in omanis: Comparison with other gulf populations and implications for disease association

This is the first comprehensive report of HLA antigens in Omanis, and the first application of HLA sequence-specific primer [SSP] DNA typing in a Gulf population. The objective was to compare the findings with other Gulf populations and assess their implications for disease association. Patients and HLA typing was carried out on 321 healthy Omanis. One hundred and twenty-six of these were typed for Class II antigens by low-resolution SSP DNA typing. The results were compared with other HLA antigen frequencies recorded from Kuwait and Saudi Arabia. The Omani population was characterized by a very high incidence of HLA-DR2 [66%], with associated HLA-DQ1 [76%] and a reduced incidence of DR4, DR7 and DR53. The incidence of DR2 is the highest recorded worldwide. HLA-A11, A32, B17, B35 and B40 were significantly higher than in Kuwait and Saudi Arabia, and A9, B21[B50] significantly lower [Pc<0.05]. HLA-B27 is very low in the Omani population [0.3%]. The high incidence of HLA-DR2 in Oman and disparities in the frequency of other antigens would indicate that there has not been any significant migration from northern Arabia. Class II DNA typing revealed that DR16 was the predominant split of DR2 [63%], with DR15 being 18% and both DR15 and 16 being found in 6%, giving a total of 87% for "DR2"-associated antigens [serology of the same individuals gave a DR2 incidence of 74%]. The major disparity between serology and DNA typing was in the definition of DR4 [serology 8%, DNA 14%] and DR51 [53% vs. 70%]. The frequency of many HLA antigens in Omanis differs significantly from frequencies found in the populations of Kuwait and Saudi Arabia, possibly reflecting different migration patterns. The high incidence of HLA-DR2 in Oman may have important implications for disease association

Kleine-Levin Syndrome: Two Cases

Kleine-Levin syndrome (KLS) is characterized by recurring episodes of hypersomnia, megaphagia, and abnormal behavior. We report two cases of KLS. Two boys, aged 18 (case 1) and 17 (case 2), had recurrent episodes of hyper-somnolence with compulsive eating or drinking and hypersexuality for several years. HLA-DR typing was HLA-DR3 and 13 in case 1 and HLA-DR4 and 10 in case 2. Case 1 showed hypersomnia with early onset of REM sleep on MSLT and frequent frontal intermittent rhythmic delta activity on EEG. Both cases showed no abnormalities on brain MRI. HLA-DR typing facilitates differentiation between KLS and narcolepsy by the absence of HLA-DR2.

Influence of HLA-DR2 phenotype on humoral immunity & lymphocyte response to Mycobacterium tuberculosis culture filtrate antigens in pulmonary tuberculosis.

Association of HLA-DR2 genes/gene products has been shown with pulmonary tuberculosis (PTB) patients in India. In the present study, the influence of HLA-DR2 and non-DR2 genes/gene products on immunity to tuberculosis has been studied. Plasma samples of -DR2 positive patients (active and inactive TB) showed a higher antibody titre to Mycobacterium tuberculosis culture filtrate antigens than non-DR2 (-DR2 negative) patients. Immunoblot analysis revealed a trend towards an increased percentage of DR2 positive patients recognizing 38, 32/34 and 30/31 kDa antigens of M. tuberculosis than DR2 negative patients. A low spontaneous lymphoproliferative response (without antigen stimulation) was seen in HLA-DR2 positive active TB patients than HLA-DR2 negative patients. However, the antigen stimulated lymphocyte response was higher in the -DR2 positive patients (active and inactive TB) when compared to non-DR2 patients. Further, an inversional correlation between antibody titre and spontaneous as well as antigen induced lymphocyte response (measured by 3H thymidine uptake and expressed as counts per minute) was seen in HLA-DR2 positive active PTB patients than non-DR2 patients. The present study suggests that HLA-DR2 genes/gene products may be associated with a regulatory role in the mechanism of disease susceptibility to tuberculosis. The genes while augmenting the humoral immune response, they suppress the spontaneous and antigen induced lymphocyte response in -DR2 positive patients with active disease.

HLA antigen profile in pulmonary tuberculosis patients & their spouses.

HLA-A, -B, -DR and -DQ antigen profile was studied in pulmonary tuberculosis patients (n = 209) and their spouses (family contacts; n = 50) and healthy volunteers (n = 72). An increased frequency of HLA-A-10, B7, B15, DR2 and DQ1 was seen in the pulmonary-TB (PTB) patients when compared to the total control subjects (n = 122). However, a significant increase was seen only with HLA-DR2 (P < 0.001; Pc < 0.01; Relative Risk 2.3) and -DQ1 (P < 0.005; Pc < 0.015; Relative Risk 2.8). Among the spouses and the corresponding patients, a similar increase of HLA-DR2 was seen. A decreased frequency of HLA-A19, B8, B17, B35, DR5 and DR6 were seen in PTB as compared to control groups. The present study suggested that HLA-DR2 and DQ1 genes/gene products may be associated with the susceptibility to tuberculosis either alone or in combination with other HLA or non-HLA genes.

Association of HLA - DR Genes with Systemic Sclerosis in Koreans / 대한류마티스학회지

OBJECTIVE: This study was conducted to elucidate the associations of HLA with systemic sclerosis (SSc) in Koreans. METHODS: HLA associations with SSc according to SSc-specific autoantibody status and clinical subsets (diffuse and limited) were investigated. HLA-A, B, and C antigens were typed by the serological method using microlymphocytotoxicity test, and HLA-DR by DNA typing method using PCR-reverse hybridization and PCR-SSCP in 56 Korean patients with SSc and 226 healthy controls. For SSc patients, anti-Scl-70 and anicentromere antibodies were tested by double immunodiffusion and indirect immunofluorescence, respectively. RESULTS: The results of HLA class I antigen typing showed that the frequencies of HLA-A24, B52 and B62 were increased, whereas those of A33, B44 and B58 were decreased in SSc patients compared to healthy controls. The frequency of HLA-DR2 was significantly increased, whereas that of HLA-DR13 was decreased in patients with SSc compared to controls. Among HLA-DR2 alleles, both HLA-DRB1*1501 and *1502 were increased in SSc patients compared to controls. According to clinical status, HLA-DRB1*1501 was increased in limited SSc patients and that of DRB1*1502 was increased both in diffuse and limited SSc patients compared to controls. According to autoantibody status, HLA- DRB1 1502 was significantly increased in anti-Scl-70-positive SSc patients and that of DRB1 1501 was increased in anti-Scl-70-negative SSc patients compared to controls. The association of HLA-DR2 alleles with SSc according to clinical subsets and anti-Scl-70 antibody status revealed that the frequency of HLA- DRB1 *1501 was significantly increased in anti-Scl-70-negative limited SSc patients compared to controls. CONCLUSIONS: These results suggest that different HLA-DR2 alleles are associated with different types of SSc in Koreans. HLA-DRB1 1502 shows strong association with anti-Scl-70-positive SSc, and DRB1 1501 with anti-Scl-70-negative limited SSc. It is concluded that the pathogenesis of SSc in Koreans is in part, based on the same genetic background.

Association of leprosy with HLA-DR2 in a Southern Brazilian population

The association between HLA specificities and leprosy was investigated in a Southern Brazilian population. One hundred and twenty- one patients and 147 controls were typed for HLA-A, B, Cw, DR and DQ. Patients were subdivided into the following subgroups, according to clinical, histological and immunological criteria: lepromatous (N = 55), tuberculoid (N = 32), dimorphous (N = 20), and indeterminate (N = 14). The frequencies of HLA specificities were compared between the total group of patients and controls, and between the same controls and each subgroup of patients. After correction of the probabilities, deviations were not significant, except for the DR2 specificity, which presented a frequency of 44.2 per cent in the total group of patients and 56.3 per cent in the subgroup of individuals with the tuberculoid form of the disease, compared to 23.3 per cent in the controls. Stratified analysis showed that the increased DR2 frequency in the total group of patients was due to the subgroups with the tuberculoid and dimorphous forms. The relative risk of tuberculoid leprosy for DR2-positive individuals was 4.2, and the etiologic fraction of DR2 was 0.429. In conclusion, a positive association of the DR2 specificity with the tuberculoid form of leprosy, but not with the lepromatous, dimorphous, or indeteterminate forms, was demonstrated in this Southern Brazilian population.

HLA-DR types in rheumatic, congenital and degenerative cardiac valve diseasesin Saudi Patients

Subjects of Saudi origin were DNA typed for HLD-DR2, DR4 and DR[w]53 by fragment-length polymorphism and amplification by sequence-specific primer techniques based on polymerase chain reaction. Of these subjects, 125 sporadic heart valve disease [96 with rheumatic heart disease, 18 with degenerate and 11 with congenital degenerate valve disease] and 77 were healthy Saudi blood donors. While the frequency of individuals typed DR[4] was about the same in the rheumatic heart disease as in the control category [30% versus 23%, respectively], it was found to be higher [55%; P< 0.02], but below the level of marginal significance after correcting for the number of DR types, in the congenital degenerate valve category. No preferential association of any DR4 subtype could be detected. The incidence of DR2 was lower in the congenital cases compared to that in the controls [9% versus 21%] and remained about the same in the rheumatic heart disease patents as in the controls. The frequency of DR[w]53 in the degenerate valve categories was slightly lower than that in the controls, but the difference was not significant. The study failed to corroborate the association between HLA-DR4 and rheumatic heart disease shown in previous studies using the sterotyping approach