Reactive arthritis in patients attending an urban sexually transmitted diseases clinic

OBJECTIVE: To assess the prevalence, clinical manifestations, associated genital infections, and HLA associations of reactive arthritis (ReA) among patients attending an urban sexually transmitted diseases (STD) clinic. METHODS: Using a standardized questionnaire, 271 consecutive adults, primarily black, with possible or proven Chlamydia trachomatis genital infection were screened for symptoms of ReA. A followup questionnaire was administered 6 weeks later by mail. Patients who reported at least 1 symptom were evaluated by a rheumatologist. HLA-B typing was performed on patients with objective ReA features. RESULTS: Nine of 217 patients (4.1%) with genital infection/inflammation had objective ReA features. Chlamydial or nongonococcal STD syndromes were diagnosed in 8 of these 9 patients (88%). Genital infection/inflammation was asymptomatic in 78% of patients with ReA features. HLA-B27 or other B7-cross-reactive group antigens were not associated with the occurrence of ReA. CONCLUSION: Nongonococcal genital infections, often asymptomatic, can trigger a relatively mild ReA in a larger number of exposed patients than previously thought, irrespective of the individual's HLA status.     

Collagen-specific cytotoxic T lymphocyte responses in patients with ankylosing spondylitis and reactive arthritis

Both ankylosing spondylitis (AS) and reactive arthritis (ReA) are strongly associated with HLA-B27 although the mechanism for this association is still unknown. Here we examine the hypothesis that B27-restricted, joint antigen-specific cytotoxic T lymphocytes (CTL) may be the driving force of AS and ReA. Type II and type XI procollagens (CII and CXI, respectively), expressed almost exclusively in the articular cartilage of the joints, were chosen as the possible targets of autoimmune CTL. Type I procollagen (CI), expressed in many different tissues, was also included as control. Nineteen nonamer peptides bearing appropriate HLA-B27 binding motifs from human CI, CII and CXI were identified and synthesized. When analyzed for binding affinity to HLA-B27 in assembly assays, four (two from CII, two from CXI) were found capable of binding to HLA-B27 with high affinity. These B27-binding collagen peptides were then used to stimulate peripheral blood lymphocytes from eight B27-positive AS and three ReA patients for identification of possible B27-restricted autoimmune CTL. HLA-B27-restricted CTL specific for one of the CII peptides, P109 were found in one of the ReA patients, but in none of the others.     

Augmentation of natural killer cell activity in mice by oral administration of transforming growth factor-beta

OBJECTIVE: To analyze the effect of HLA-DR genes on susceptibility to and severity of ankylosing spondylitis (AS). METHODS: Three hundred sixty-three white British AS patients were studied; 149 were carefully assessed for a range of clinical manifestations, and disease severity was assessed using a structured questionnaire. Limited HLA class I typing and complete HLA-DR typing were performed using DNA-based methods. HLA data from 13,634 healthy white British bone marrow donors were used for comparison. RESULTS: A significant association between DR1 and AS was found, independent of HLA-B27 (overall odds ratio [OR] 1.4, 95% confidence interval [95% CI] 1.1-1.8, P = 0.02; relative risk [RR] 2.7, 95% CI 1.5-4.8, P = 6 x 10(-4) among homozygotes; RR 2.1, 95% CI 1.5-2.8, P = 5 x 10(-6) among heterozygotes). A large but weakly significant association between DR8 and AS was noted, particularly among DR8 homozygotes (RR 6.8, 95% CI 1.6-29.2, P = 0.01 among homozygotes; RR 1.6, 95% CI 1.0-2.7, P = 0.07 among heterozygotes). A negative association with DR12 (OR 0.22, 95% CI 0.09-0.5, P = 0.001) was noted. HLA-DR7 was associated with younger age at onset of disease (mean age at onset 18 years for DR7-positive patients and 23 years for DR7-negative patients; Z score 3.21, P = 0.001). No other HLA class I or class II associations with disease severity or with different clinical manifestations of AS were found. CONCLUSION: The results of this study suggest that HLA-DR genes may have a weak effect on susceptibility to AS independent of HLA-B27, but do not support suggestions that they affect disease severity or different clinical manifestations.     

Remote fetal medicine consultation using stored ultrasound video images

Fifty-four (54) unrelated patients with Mediterranean Kaposi's sarcoma (MKS) and 8 patients members of 4 unrelated families with familial MKS were serotyped for HLA-A,B and DR antigens. The diagnosis was histologically confirmed and all patients were negative for anti-HIV antibodies. An increased frequency of HLA-B18 (44.4% vs 14.2% in the controls, p < 0.001, RR = 4.8) and HLA-DR5 (57.6% vs 37.2% in the controls, p < 0.025, RR = 2.29) was observed in the group of patients with MKS. Seven (7) of the 8 family members with FMKS possessed HLA-DR5, and the affected members in the 3 families shared a common haplotype which included HLA-DR5. These findings support the hypothesis that genetic factors linked to HLA-DR5 antigen may contribute to the pathogenesis of MKS.     

HLA-C genes and susceptibility to type 1 autoimmune hepatitis

Susceptibility to autoimmune hepatitis (AIH) is associated with the HLA A1-B8-DR3 haplotype, DR4 antigen, and, more specifically, the HLA DRB3*0101, DRB1*0301, and DRB1*0401 alleles. Few investigators, however, have examined the HLA C locus in AIH, which warrants detailed study in view of its recently described roles in immunoregulation. Eighty-seven adult, white patients with well-characterized type 1 AIH and 100 controls were studied. HLA C and HLA DRB1 alleles were assigned by polymerase chain reaction (PCR)-based genotyping. HLA A and B antigens were determined by standard microlymphocytotoxicity assay. Extended haplotypes were constructed according to known patterns of linkage disequilibrium. Only one HLA C locus allele, Cw*0701, which was present in 54% of patients versus 34% of controls (P = .006; relative risk [RR] = 1.54) was associated with AIH. The overall increase in the frequency of the Cw*07 gene (70.1% of patients vs. 54% of controls; P = .024; RR = 1.3) was due entirely to inheritance of the Cw*0701 allele rather than the other Cw*07 alleles, Cw*0702, *0703, and *0704. The RR for Cw*0701 (RR = 1.54) is greater than that for HLA A1 (RR = 1.33) and DRB1*0301 (RR = 1.49), but less than that for HLA-B8 (RR = 1.75). The present findings suggest that the gene or genes conferring susceptibility to AIH lie in the region centromeric to the HLA A locus between HLA C and DRB1. Although linkage disequilibrium with both B8 and DRB1*0301 may account for our finding of an increased frequency of Cw*0701, it is also possible that this allele contributes to disease susceptibility, perhaps by interaction with natural killer cells or cytotoxic T lymphocytes.     

Fontanel ultrasonography of purulent meningitis in children in Abidjan (Ivory Coast)

Reactive arthritis (ReA) is one of the most common arthritides affecting young adults. In most cases it follows urogenital or enteric bacterial infection, but its pathogenesis is not fully understood. It is generally considered a sterile arthritis which appears to involve immune response to bacterial organisms and genetic host susceptibility associated with the presence of HLA-B27 antigen. New findings suggest that in some ReA cases, viable bacteria are present inside the joints, and these organisms may cause the disease and trigger the inflammatory response. ReA manifests clinically as a rheumatoid factor negative oligoarthritis associated with enthesopathy and certain mucosal and skin lesions. Laboratory findings in ReA are non-specific. Although concepts of its pathogenesis are still evolving, so-called ReA remains an important condition to be distinguished from rheumatoid arthritis. Prognosis is generally better. Treatments with known effects in some cases include non-steroidal anti-inflammatory drugs, intra-articular corticosteroids, oral tetracyclines and sulphasalazine. The occasional chronic and severe ReA may be very difficult to treat.     

Overlapping peptide-binding specificities of HLA-B27 and B39: evidence for a role of peptide supermotif in the pathogenesis of spondylarthropathies

OBJECTIVE: Previous studies indicated the increase of HLA-B39 among HLA-B27 negative patients with spondylarthropathies (SpA). This study was performed to examine whether the natural ligands of HLA-B27 are capable of binding to HLA-B39. METHODS: Peptides were synthesized according to the sequences of known natural ligands of HLA-B27 or B39 and were tested for their binding to HLA-B*3901 and B*2705 by quantitative peptide binding assay, using a TAP-deficient RMA-S cell line transfected with human beta2-microglobulin and HLA class I heavy chain genes. RESULTS: Four of the 10 HLA-B27 binding peptides significantly bound to HLA-B*3901. All 4 peptides had hydrophobic/aromatic amino acids (Leu or Phe) at the C-terminus. In contrast, peptides with basic residues (Lys, Arg) or Tyr at the C-terminus did not bind to B*3901. In parallel experiments, 1 of the 2 natural ligands of HLA-B*3901 was found to bind to B*2705. CONCLUSION: A subset of natural HLA-B27 ligands was capable of binding to B*3901. In addition to Arg at position 2 (Arg2), hydrophobic/aromatic C-terminal residues, such as Leu or Phe, seemed to be crucial for the cross-specificity. These results suggested that HLA-B27 and B39 recognize overlapping peptide repertoires, supporting the hypothesis that the peptides presented by both of these class I antigens play a role in the pathogenesis of SpA.     

Is immunogenetic susceptibility to neuropsychiatric systemic lupus erythematosus (SLE) different from non-neuropsychiatric SLE?

OBJECTIVES: To analyse frequency of HLA class II antigens (DR and DQ) and lymphocytotoxic autoantibodies in patients with systemic lupus erythematosus (SLE) and subsets with or without neuropsychiatric involvement. METHODS: Ninety three patients with SLE (42 with neuropsychiatric features) were typed for HLA class II antigens and investigated for the presence of lymphocytotoxic autoantibodies by a complement dependent microlymphocytotoxicity assay. A total of 191 controls of similar ethnic background were also typed for HLA antigens. RESULTS: HLA-DR3 antigen was increased in the total group of patients with SLE (p = 0.003) and in the neuropsychiatric group (p = 0.002). HLA-DR4 antigen frequency was increased in non-neuropsychiatric patients (p = 0.001) and decreased in patients with neuropsychiatric SLE (p = 0.0005). Comparisons of HLA frequencies between subgroups of patients showed decreased HLA-DR4 (p < 0.0001) and increased HLA-DR9 and HLA-DQ2 antigens (p = 0.0008 and 0.005 respectively) in the neuropsychiatric group. The frequency of lymphocytotoxic autoantibodies was increased in neuropsychiatric patients with SLE having HLA-DR9 specificity (p = 0.04). CONCLUSION: HLA-DR4 may have a protective specificity for the development of neuropsychiatric features of SLE and HLA-DR9, in addition to HLA-DR3, and the presence of lymphocytotoxic auto-antibodies may predispose to neuropsychiatric abnormalities.     

HLA markers and progression in psoriatic arthritis

OBJECTIVE: To investigate whether the addition of all serologically defined HLA antigens to a baseline model further influences the predisposition to disease progression in psoriatic arthritis (PsA). METHODS: Patients with PsA followed prospectively over 19 years were studied. Clinical and laboratory assessments of both active inflammation and clinical damage were performed at 6 month intervals according to a standard protocol. Progression of damage was defined as transition to higher damage states defined by the number of damaged joints. A model that provides estimates of the ratio of transition rates for an individual with the antigen versus one without, and examines the antigen effect on each of the 3 transition rates, was used. HLA antigens were examined in groups by loci under the assumption of common effects across transitions when added to the basic model. The significance levels were examined in comparison with Bonferroni type corrections. Likelihood ratio chi-squared statistics were used as a basis for the significance levels. In total, 292 patients with PsA were included in the study. RESULTS: Only HLA-B22 was added to the original model, which includes HLA-B39, providing risk for progression in early stages, HLA-B27 in the presence of HLA-DR7 providing risk for progression through all states, and DQw3 providing increased risk in the absence of DR7, while in the presence of DR7 it provides "protection." HLA-B22 provides protection from disease progression through all states. CONCLUSION: This study extends our report that HLA antigens serve as markers for disease progression in PsA.     

Spondyloarthropathy and human immunodeficiency virus infection in Zambia

OBJECTIVE: To explore the relationship between spondyloarthropathy (SpA) and infection with the human immunodeficiency virus (HIV) in black Zambians. METHODS: Consecutive patients attending an arthritis clinic in a 30 month period were assessed clinically and tested for the presence of antibodies to HIV. HLA-B27 gene was investigated by polymerase chain reaction and T cell subsets were tested in selected subgroups. RESULTS: Of 595 new attendees, 272 were diagnosed with SpA [130 reactive arthritis (ReA), 128 undifferentiated SpA (uSpA), 13 psoriatic arthritis (PsA), 1 ankylosing spondylitis] and 146 with a reactive type arthritis alone (AA) without preceding clinical trigger infection or SpA features. HIV seroprevalence was 98% in uSpA, 94% PsA, 87% ReA, 64% AA; vs approximately 50% among hospital outpatients and 30% of the adult urban population. Prevalence of SpA is calculated at approximately 180/100,000 in HIV positive and approximately 15/100,000 in HIV negative in the general population. Dysentery was the most common identified trigger. Positive HIV status correlated strongly with SpA features and aggressive sustained disease. At onset 80% of patients were in WHO clinical stage 1 (no disease or lymphadenopathy alone), with a mean CD4+ count of 279/microl. Stage 4 patients had a mean CD4+ count of 60/microl and inactive arthritis. The B27 gene was absent in 30 patients tested. CONCLUSION: ReA is the most common inflammatory joint disorder in black Zambians and is closely linked to HIV infection and not B27, even though our subjects had clinical and radiological characteristics similar to those reported in HLA-B27 positive Caucasians. The changing epidemiology of SpA in this region has important practical and educational implications.     

CMV-specific immune responses and HLA phenotypes of AIDS patients who develop CMV retinitis. HNRC Group. HIV Neurobehavioral Research Center

HLA phenotype and immune responses to CMV were studied to determine whether the subset of AIDS patients who developed CMV retinitis were immunogenetically or immunologically predisposed. CMV retinitis develops in approximately 28-35% of AIDS patients and CMV encephalitis develops in 40% of those with retinitis, often leading to death. T-cell proliferation responses to CMV and HIV were assayed prospectively in individuals enrolled in a longitudinal study at the HIV Neurobehavioral Research Center (HNRC) in San Diego. Seventy-three participants, at various stages of disease, have been HLA typed and followed, clinically and immunologically, for up to 5 years. Six HIV infected individuals who eventually developed CMV retinitis, and were assayed prospectively, had a history of low T-cell proliferation to CMV antigens before they were profoundly immunosuppressed. All 10 individuals with CMV retinitis had at least one of three HLA alleles (or combinations): A2B44 (p = 0.02), B51(p = 0.02), or DR7 (p = 0.01) (collective p value = 0.007). Three of the 10 had two or more of these alleles. Of AIDS patients with CD4 counts below 100 and actively at risk for retinitis, 7/15 with A2B44,51, or DR7 have developed retinitis compared to 0/13 without these HLA alleles (relative risk = 23.8). All 4 patients with these alleles who have died, had retinitis. These results suggest that HIV infected individuals with HLA phenotypes A2B44, B51, and DR7 have low T-cell immune responses to CMV and are predisposed to CMV retinitis and encephalitis as immunodeficiency progresses.     

The role of HLA-B27 polymorphism and molecular mimicry in spondylarthropathy

Ankylosing spondylitis (AS), reactive arthritis (ReA) and other related spondyloarthropathies (SpAs) are characterized by a strong association with the major histocompatibility complex allele HLA-B27. Experimental evidence from humans and transgenic rodents suggests that HLA-B27 is itself involved in the pathogenesis of SpA. Population and peptide-specificity analysis of HLA-B27 suggest it has a pathogenic function related to antigen presentation. Putative roles for infectious agents have been proposed in ReA and suggested in AS. However, the mechanism by which HLA-B27 and bacteria interact to induce arthritis is not clear. Molecular mimicry between bacterial epitopes that cross-react with self-B27 peptides is the most persuasive explanation for the pathogenesis of SpA. The experimental studies reviewed here have greatly increased our knowledge of the structure, function and disease association of HLA-B27.     

"The sarcoidosis map": a joint survey of clinical and immunogenetic findings in two European countries

We pooled immunogenetic data obtained in independent studies in two European populations (Italian and Czech) of patients affected by sarcoidosis. Correspondence analysis was used to investigate the associations between clinical and immunogenetic data. Two hundred and thirty-three patients were enrolled in the study, of which 126 were from the Czech Republic and 107 from Italy. Using a common protocol, we examined each patient for sex, age of disease onset, roentgenologic stage, extrapulmonary spread, and clinical course. One thousand and ten healthy individuals, HLA typed for class I and II serologic polymorphisms, served as controls. Findings that were essentially in agreement in both populations were: (1) a positive association of sarcoidosis with HLA-A1, B8, and DR3 markers, and a negative association with HLA-B12 and DR4; (2) a prevalence of HLA-DR3 and DR4 among females and of DR5 among males; (3) a relationship of B13 and B35 with early onset and of A30, B8, DR3, and DR4 with late onset of disease; (4) an association of B27 with sarcoidosis restricted to the lungs; (5) a relationship of A1, B8, B27, and DR3 to roentgenologic stage I and of B12 and DR4 to stage III; and (6) an association of HLA-DR3 with a good outcome. Population-restricted findings essentially concerned the alleles HLA-B13 and B22, the former being associated with the disease, male sex, early onset, extrapulmonary localization and relapse only in Czechs, and the latter to disease spread only in Italians. Our results seem to support the concept that immunogenetic background may at least partly account for the clinical heterogeneity of sarcoidosis.     

Polysaccharide biotechnology--a Cinderella subject

Histotyping of HLA I antigens in 100 patients with keratoconus. Europeoids of the Chelyabinsk district, and of 701 controls (donors listed in the regional register) showed an increased incidence of HLA A28, B12, and B15, a decreased incidence of HLA B8, B13, and complete absence of HLA A11. Estimation of HLA haplotypes in keratoconus showed an increased incidence of haplotypes A1-B5 (relative risk RR = 5.9), A2-B15 (RR = 3.34), A2-B27 (RR = 2.12), and A9-B21 (RR = 4.13) and decreased incidence of A1-B8 (RR = 0.31). The incidence of incomplete phenotypes was 27%. The most incident of incomplete phenotypes was A3-B35. Reliably linked HLA haplotypes A3-B7, A2-B27, A9-B21, and A9-B35 were typical of men with keratoconus, whereas A2-B21 haplotype was characteristic of the female patients.     

Neonatal pemphigus vulgaris associated with mild oral pemphigus vulgaris in the mother during pregnancy

PURPOSE: Autoimmunity has been proposed to play a role in the pathogenesis of the abdominal aortic aneurysm (AAA). Several autoimmune diseases are associated with specific HLA DR alleles. These experiments were carried out to determine whether the same HLA DR types that have been reported to be associated with AAA in a mixed North American population are similarly associated with AAA in a more homogeneous group of patients in Japan. METHOD: HLA DR typing was performed by a serologic method on samples of peripheral blood of patients with nonspecific infrarenal AAA in Nagasaki University Hospital in Japan. The frequencies of HLA DR antigens were compared with those of volunteers approximately matched for age and sex from the same referral area. RESULTS: HLA DR haplotypes were determined in 46 Japanese patients with AAA and in 50 patients in a control group. The HLA-DR2(15) antigen was observed in 27 (58.7%) patients (29 alleles 31.5%) with AAA and in 14 (28%) subjects (16 alleles 26.0%) in the control group (p < 0.005). CONCLUSIONS: The data suggest that HLA-DR2(15) has an important role as a genetic risk factor for AAA in Japanese patients, as previously reported in a mixed North American population.     

Histocompatibility antigens in multiple sclerosis in children

A phenotyping was done in respect of HLA system in 14 children with documented multiple sclerosis (MS), 20 children with potential MS, and 42 their near relations. HLA-B12 antigen was recordable with high frequency (RR = 6.29; P < 0.025) while HLA-B18 with low one (P < 0.01) as compared to normal subjects both among patients in the general group and in those with proved MS. The latter showed a tendency toward increase in frequency HLA-B7. Children with significant MS where there was an association in the phenotype of HLA-B12 or HLA-B7 with HLA-A3 ran predominantly an aggravating course while their association with HLA-A2 resulted in a more benign course. The results obtained in respect of HLA antigens in MS in children differ from those of other authors on MS in adults.     

HLA association and occurrence of autoantibodies in Asian-Indian patients with ulcerative colitis

OBJECTIVES: The purpose of the present study was to determine the profile of HLA class I antigens, antinuclear antibodies (ANA), and antineutrophil cytoplasmic antibodies (ANCA) in ulcerative colitis (UC) patients from Northern India. METHODS: The study consisted of 100 UC patients with or without extraintestinal manifestations. Data on HLA, ANA, and ANCA were analyzed with respect to age at onset, sex, duration of disease, and occurrence of extraintestinal manifestations, and data were correlated with those of healthy controls from the same population. RESULTS: The most common extraintestinal manifestations in order of occurrence were arthralgia (53.8%), ocular lesions (18%), sacroiliitis (12.7%), hepatobiliary (7.7%), cutaneous (5%), and vascular (2.6%). ANA and ANCA were positive in only 3% of cases. Of the HLA class I antigens, HLA-A19 was significantly increased in UC patients compared with controls (63.4% vs. 33.5%, p < 0.001, RR = 3.4), particularly its subtype HLA-A33 (20.7% vs. 4%, p < 0.001, RR = 6.3). There was no deviation in the frequency of HLA-B locus antigens, whereas HLA-Cw6 was increased significantly in patients compared with controls (14.6% vs. 3.5%, p < 0.001, RR = 4.4). CONCLUSIONS: The occurrence of extraintestinal manifestations in Indian patients with UC is similar to that reported elsewhere, although ANA and ANCA positivity is lower. HLA studies revealed that A19(33) and Cw6 are associated with UC.     

Guillain-Barré and Fisher's syndromes subsequent to Campylobacter jejuni enteritis are associated with HLA-B54 and Cw1 independent of anti-ganglioside antibodies

The frequencies of human leukocyte antigens (HLA)-class I (A, B and Cw) were determined serologically and those of HLA-class II (DRB1 and DQB1) at the genomic level in 35 Japanese patients with Guillain-Barré syndrome (GBS), 58 with Fisher's syndrome (FS), and 112 healthy controls. HLA-B54 and -Cw1 antigens were found in GBS and FS patients from whom Campylobacter jejuni had been isolated more often than found in the healthy controls. No HLA types were related to GBS or FS as a whole, except for the B54 antigen which often was significant in the entire GBS group. This relation, however, may depend on the high population of C. jejuni-isolate patients in our GBS group. There were no relationships between the frequencies of HLA types and the presence of serum IgG antibodies to GM1, GQ1b, GD1a, or GalNAc-GD1a. Our findings suggest that HLA types are associated with the onset of GBS and FS after C. jejuni enteritis and that the HLA types in distinct GBS and FS subgroups of a single etiological origin need to be examined.     

Contribution of HLA genes to genetic predisposition in diffuse panbronchiolitis

Diffuse panbronchiolitis (DPB) in East Asia is a distinctive chronic obstructive pulmonary disease of unknown etiology. We hypothesize that the disease susceptibility is due to genetic predisposition unique to Asians. Association between human leukocyte antigen (HLA)-Bw54 and the disease was previously reported. In the present study, using newly developed polymerase chain reaction (PCR)- based methods, we directly analyzed HLA class I and II alleles in 76 Japanese patients. HLA-A, -B, and -C antigens were screened by the conventional typing method, and then B22-group alleles including HLA-B54 were genotyped by single-strand conformation polymorphism analysis. Alleles of HLA-DRB1 gene were fully determined by the microtiter plate hybridization method. Thirty-seven percent of the patients possessed HLA-B*5401 allele conserved predominantly in East Asians, as compared with 15% of 110 healthy volunteers (chi2 = 12.4, p = 0.0004). In addition, 4% of the patients possessed B*5504 also unique to Asians but a rare allele which was not found in normal control subjects in this study. Typing of HLA-DRB1 class II gene did not demonstrate strong positive association with the disease. A33, B44, and DRB1*1302 showed negative association with the disease. We conclude that distinctive molecular structure of HLA-B alleles or a closely linked gene in the HLA region contributes to genetic predisposition in diffuse panbronchiolitis. This may partly explain why this disorder is found primarily in Asians.     

The primary physician and the family with a handicapped or chronically ill child

BACKGROUND: Multiple evanescent white dot syndrome (MEWDS) is a benign acquired isolated chorioretinal disorder. Symptoms include photopsia, visual blur and scotomas. Ocular examination reveals multiple white dots at the level of the deep retina. A parainfectious disorder was suggested but the exact mechanism of MEWDS is still unknown. Postulating that MEWDS might be an antigen driven inflammatory reaction, we analyzed HLA subtypes in patients with MEWDS. PATIENTS AND METHODS: Sixteen patients were diagnosed with MEWDS in Lausanne from 1985 to 1994. Blood was withdrawn in 9/16 patients. HLA-A, -B and -DR were sought. RESULTS: HLA-B51 was detected in 4/9 patients (44.4%). Other HLA subtypes were detected sporadically. CONCLUSIONS: The frequency of HLA-B51 haplotype was found to be 3.7 times more elevated than in a normal control caucasian group. This suggests the possibility that MEWDS might be a genetically determined disorder as it is the case for other ocular diseases like Birdshot chorioretinopathy (HLA-A29), Harada's disease (HLA-DRMT3), acute anterior uveitis (HLA-B27) or Beh?et's disease (HLA-B51). We have no explanation for the presence of HLA-B51 in both Beh?et's disease and MEWDS. The association of HLA-B51 and MEWDS needs confirmation by further testing.