Limited usefulness of antithyroperoxidase and antithyroglobulin assays in Jamaicans with Graves' disease

The clinical usefulness of commercially prepared haemagglutination kits for thryro peroxidase (TPO) antibody and thyroglobulin (TG) antibody was evaluated in 145 consecutive Jamaicans with Graves' disease. Sixty two (43 percent) of the patients were newly diagnosed, 12 (8 percent) were in remission and 71 (49 percent) had relapsed. Sera from 65 (45 percent) patients were positive for thyroid antibodies. The TPO antibodies were found in 43 percent (63/145), thyroglobulin antibodies in 12 percent (17/145) fifteen (10 percent) patients had both anti-TPO and TG antibodies. Similar prevalences of TPO antibody were found in newly diagnosed patients and those who had relapsed (44 percent v. 41 percent) but the prevalence in the patients in remission was significantly higher (75 percent; X2 = 4.8, P <0.05). The prevalence of TPO antibody increased significantly with age at onset before age 35 years compared to later onset (56 percent v. 32 percent; X2 = 8.09, P <0.005). The presence of both TPO antibody (64 percent v. 31 percent; X2 = 13.1, P <0.001) and TG antibody (22 percent v. 6 percent; X2 = 8.8, P <0.005) correlated positively with Graves' opthalmopathy. Neither of the tests was adequately sensitive in detecting GD in Jamaicans. (AU)

Clinical usefulness of thyroid autoantibodies in patients with Graves' disease

The prevalence of thyroid antibodies varies with the population studied. It has been suggested that the presence of anti-thyroid microsomal (TMAb)/thyroid peroxidase (TPO) antibodies and anti-thyroglobulin antibodies (TgAB) may predict clinical parameters including anti-thyroid drug therapy outcome in Graves' disease. Commercially available kits were used to measure anti-TPO and Tgab titres. Antibody titres were compared in the following clinical groups: newly diagnosed (n=21), treated with radioactive iodine (n=2), remission (n=22), relapse (n=27), chronic (n=44). Anti-thyroglobulin antibodies were present in 10.3 percent (10/97) of the patients with titres ranging from 40 to 320 with a geometric mean titre of 80. Ant-TPO antibodies were found in 49.4 percent (48/97) with titres ranging from 100 to 102, 400 and a geometric mean titre of 1,800. The presence and titres of thyroid antibodies did not correlate with age at diagnosis, duration of disease, cardiac complications, other concommitant autoimmune diseases, antithyroid drug therapy or the relapse or remission rate. The results of this study did not indicate any clinical usefulness of thyroglobulin and thyroid peroxidase beyond diagnosis in Graves' disease.(AU)

Systemic lupus erythematosus, rheumatoid arthritis and HLA phenotypes in Jamaicans

The HLA phenotypes were investigated in 30 Jamaican patients with systemic lupus erythematosus (SLE), 30 with rheumatoid arthritis (RA) an d forty healthy controls. HLA phenotypes were determined by the microcytotoxicity technique, using commercially prepared typing trays. In this study, the HLA phenotypic associations with SLE (HLA-B14, RR 4.3: HLA-A28, RR 4.3) were not statiscally significant. However, a statistically significant lack of HLA-A9 (p<0.01;CP<0.1) was observed in SLE patients compared to healthy controls. In RA patients, a statistically significant associations was noted with HLA-A2 (RR5.1; CP<0.01). No HLA class 11 associations were noted with SLE. Class 11 associations with RA did not achieve statistical significance but included those previously established in other populations. The preliminary data obtained from this study indicate differences in the patterns of HLA phenotypes in Jamaican patients with SLE and RA compared to those observed in such patients elsewhere. Further studies involving larger groups of patients and typing at the serological, cellular and molecular levels are clearly warranted (AU)

Systemic lupus erythematosus, rheumatoid arthritis and HLA phenotypes in Jamaicans

The HLA phenotypes were investigated in 30 Jamaican patients with systemic lupus erythematosus (SLE), 30 with rheumatoid arthritis (RA) an d forty healthy controls. HLA phenotypes were determined by the microcytotoxicity technique, using commercially prepared typing trays. In this study, the HLA phenotypic associations with SLE (HLA-B14, RR 4.3: HLA-A28, RR 4.3) were not statiscally significant. However, a statistically significant lack of HLA-A9 (p<0.01;CP<0.1) was observed in SLE patients compared to healthy controls. In RA patients, a statistically significant associations was noted with HLA-A2 (RR5.1; CP<0.01). No HLA class 11 associations were noted with SLE. Class 11 associations with RA did not achieve statistical significance but included those previously established in other populations. The preliminary data obtained from this study indicate differences in the patterns of HLA phenotypes in Jamaican patients with SLE and RA compared to those observed in such patients elsewhere. Further studies involving larger groups of patients and typing at the serological, cellular and molecular levels are clearly warranted

Seroprevalence of autoantibodies in selected and unselected populations in Jamaica

Various serological techniques were used to investigate the prevalence and distribution of autoantibodies in healthy Jamaicans and patients with autoimmune and non-autoimmune disease. Low concentrations of autoantibodies were found in healthy Jamaicans, including thyroid (1.5 percent), gastric parietal cell (1.4 percent) and smooth muscle (11.3 percent). There was no significant age or sex predominance in the distribution of autoantibodies in the healthy population though autoimmune disease was more prevalent in females. Serological overlaps occurred but the comparative distributions and concentrations of autoantibodies in patients with autoimmune disease and non-autoimmune disease, and health subjects indicate that currently available methods of autoantibody determination may be used successfully in diagnosis in Jamaica. Failure to detect circulating pancreatic islet cell antibodies in insulin-dependent diabetic patients as well as in healthy Jamaicans questions the pathogenicity of these antibodies and diminished their diagnostic usefulness in this population. (AU)

Seroprevalence of autoantibodies in selected and unselected populations in Jamaica

Various serological techniques were used to investigate the prevalence and distribution of autoantibodies in healthy Jamaicans and patients with autoimmune and non-autoimmune disease. Low concentrations of autoantibodies were found in healthy Jamaicans, including thyroid (1.5 per cent ), gastric parietal cell (1.4 per cent ) and smooth muscle (11.3 per cent ). There was no significant age or sex predominance in the distribution of autoantibodies in the healthy population though autoimmune disease was more prevalent in females. Serological overlaps occurred but the comparative distributions and concentrations of autoantibodies in patients with autoimmune disease and non-autoimmune disease, and health subjects indicate that currently available methods of autoantibody determination may be used successfully in diagnosis in Jamaica. Failure to detect circulating pancreatic islet cell antibodies in insulin-dependent diabetic patients as well as in healthy Jamaicans questions the pathogenicity of these antibodies and diminished their diagnostic usefulness in this population.

Prevalence of reactive serological tests for syphilis in the Jamaican population

Serological tests for syphilis (STS) were performed on sera from 15,876 members of the general adult population, 3,039 pregnant women and 1,029 children, in order to assess the prevalence and value of reactive STS in Jamaicans; 2.7 percent of sera from the general adult population, 4.7 percent from pregnant women and 2.2 percent from children were reactive in the Venereal Disease Research Laboratory (VDRL) test. Reactive Flourescent Treponemal Absorption (FTA-ABS) tests occurred in significantly higher frequency in pregnant women (4 percent ) than in the general population (2.2 percent; p<0.001). The prevalence of reactive STS in children did not differ significantly from that of the general adult population. The predictive value of a reactive VDRL test in pregnant women (85 percent) was higher than that of the general population (79 percent). These results suggest that inadequate screening with the inexpensive VDRL test would enable the early detection and treatment of syphilis, and could prevent increasing incidence of congenital syphilis in Jamaica (AU)

Diagnosis of neurosyphilis: a critical assessment of current methods

Clinical features of 74 patients with neurosyphilis and 38 syphilitic patients with nonsyphilitic neurologic disorders were correlated with results of their serum and cerebrospinal fluid (CSF) VDRL and FTA tests, and with the WBC count and total protein level in the CSF. The most common clinical features in those having neurosyphilis were reflex changes (53.9 percent), peripheral neuropathy (44.5 percent), ataxia (38 percent), and cranial nerve palsies (24.3 percent). In 27 percent of the patients with neurosyphilis the CSF was VDRL-reactive, while in 77 percent the CSF was FTA-reactive. The frequency of elevated WBC counts in various serologic categories ranged from 23 percent to 27 percent; neither the mean WBC count nor the protein level differed significantly among the different serologic categories (P less than .05). Only two of the 74 patients with neurosyphilis and elevation of both the WBC and protein level. None of the syphilitic patients without neurosyphilis had an elevated WBC or protein level, though the CSF was FTA-reactive in all 38. Among the neurosyphilis patients whose CSF was VDRL-nonreactive but FTA-reactive, 21 percent had an elevated protein level and 26 percent had an elevated WBC count. These results support the view that patients having neurosyphilis will not necessarily have either VDRL-reactive CSF or the other expected CSF abnormalities. (AU)

Diagnostic tests in rheumatology

The diagnosis of the rheumatic disorders may be easy or may be complicated; some clinical syndromes overlap considerably, some laboratory tests may be equivocal. However, a judicious mix of clinical features and laboratory as well as radiological data will in most cases lead to a satisfactory working diagnosis (AU)

Reye's Syndrome

Reye's syndrome is a potentially life-threatening condition which may suddenly develop in a child who appears to be getting better from a previous viral illness. The child will usually have been given aspirin for fever and/or pain. Clinical features are vomiting and signs of encephalopathy which may lead to irreversible morbidity and even death. The incidence/prevalence of Reye's syndrome in Jamaica is not known, one case having been documented in 1979. On the other hand, aspirin usage is extremely common. While it is clear that not all children who use aspirin will get Reye's syndrome it is equally clear that early or mild forms of the illness may be misdiagnosed or completely missed unless those involved in medical practice are aware of what to look for and indeed look for the particular features. In the meantime, it would be prudent to accept the experience of others who have found an indubitable link with aspirin and to limit the use of this drug in children under twelve years of age. This is indeed the recommendation of the Committee of Safety of Medicines (CSM) in the UK, which has written to doctors and pharmacists advising them of these conclusions (AU)