A case of familial dysalbuminemic hyperthyroxinemia (FDH) in Japan: FDH as a possible differential diagnosis of syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH).

Familial dysalbuminemic hyperthyroxinemia (FDH) is an autosomal dominant condition and is the most commonly inherited euthyroid hyperthyroxinemia in Caucasians. However, it is extremely rare in Asian populations. A 30-year-old Japanese woman, who was incidentally found to have apparent thyroid dysfunction, was admitted to our hospital in 2004. She had extremely elevated serum free thyroxine (FT4), moderately elevated free triiodothyronine (FT3), and normal thyroid-stimulating hormone (TSH). Clinical thyroid examination revealed no abnormalities other than small goiter. Anti-thyroglobulin antibody titer was positive, but titers of other anti-thyroid antibodies, including antithyroid peroxidase antibody, TSH receptor antibodies, and thyroid-stimulating antibody, were negative. Levels of FT3, FT4, and TSH were similar when measured by three different laboratory kits, and FT4 was still high when measured by equilibrium dialysis. By affinity chromatography, FT4, TT4, and albumin were extracted to the same fraction, and the levels of FT4 and TT4 were extremely high. By combination of reversed phase liquid chromatography and mass spectrometry techniques, the amino acid sequence of human serum albumin was determined. The patient was found to be a heterozygote for p.R218P mutation in the gene for human serum albumin and was diagnosed as FDH. This patient, who harbored the p.R218P mutation in the albumin gene, is the fifth case report of FDH in Japan. This condition is characterized by extremely high serum FT4 and moderately high serum FT3 levels. Although rare, FDH should be considered in the differential diagnosis for syndrome of inappropriate secretion of TSH (SITSH) in Japan.

Hepatotoxicity and cutaneous reactions after antithyroid drug administration.

OBJECTIVE: Use of the antithyroid drugs (ATDs) thiamazole (MMI) and propylthiouracil (PTU) is associated with a high frequency of side effects. When patients experience side effects with one (the 1st) ATD, it is usually discontinued and another is administered (the 2nd ATD). We investigated side effects associated with the 1st and 2nd ATDs. DESIGN AND PATIENTS: Four hundred forty-nine patients with untreated Graves' disease (GD) were randomly assigned to three groups according to ATD type and/or dosage: 15 mg/day MMI, 30 mg/day MMI and 300 mg/day PTU. The type, frequency and onset of side effects were assessed. We also studied the side effects associated with the 2nd ATD after cessation of the 1st ATD. MEASUREMENTS: Cutaneous reactions, liver dysfunction and other side effects were examined every 2 weeks after starting ATD administration. RESULTS: The overall frequency of side effects in patients taking 15 mg/day MMI was low. The frequencies of cutaneous reactions in patients taking 30 mg/day MMI and hepatotoxicity in those taking 300 mg/day PTU were high. Hepatotoxicity developed later than cutaneous reactions with PTU. Hepatotoxicity developed earlier in the 30 mg/day MMI group than in the other two groups. The frequency of side effects did not differ between the 2nd and 1st ATDs. Hepatotoxicity occurred at a higher frequency in patients who were switched from MMI to PTU because of hepatotoxicity of the former. CONCLUSION: Attention to the onset times of side effects and cross-reactivity of ATDs can lead to safer treatment of GD.

Clinicopathological features of 171 cases of primary thyroid lymphoma: a long-term study involving 24553 patients with Hashimoto's disease.

There are few large-scale reports of primary thyroid lymphoma (PTL). This study clinically and pathologically reviewed 171 patients with PTL and 24,553 patients with Hashimoto's disease at Ito Hospital between January 1990 and December 2004, to investigate the clinical features and the treatment outcomes of PTL. The median age of the patients with PTL was 67 years (range, 27-90 years). The pathological diagnosis of PTL patients included diffuse large B-cell lymphoma (DLBCL) (n=74), DLBCL with mucosa-associated lymphoid tissue (MALT) lymphoma (n=13), MALT lymphoma (n=80) and others (n=4). Of the 167 patients with B-cell lymphoma, treatment included combined modality therapy (CMT) (n=95), radiation therapy (RT) alone (n=60) and chemotherapy alone (n=6). Information on treatment was not available in six patients. Information on treatment response was available in 154 patients; 149 patients (97%) responded to treatment. According to the institutional treatment strategy of Ito Hospital, 45 of 54 patients with stage IE disease received RT alone, and 87 of 113 stage IIE patients received CMT. The 5-year overall survival rate was 85% (95% confidence interval, 79-91%). This study demonstrated that PTL showed good response to radiotherapy and chemotherapy and had a favourable prognosis.

TRAF6 negatively regulates TNFalpha-induced NF-kappaB activation.

TNF receptor-associated factor 6 (TRAF6) is an essential adaptor protein for the Interleukin-1 (IL-1) signaling pathway; however, its role in the signaling of another proinflammatory cytokine, tumor necrosis factor alpha (TNFalpha, has not been explored. Interestingly, we observed that TNFalpha-induced expression of IL-6, CXCL1 and granulocyte macrophage colony stimulating factor (GM-CSF) were significantly enhanced in TRAF6-deficient MEFs. Compared to those observed in wild-type MEFs, TNFalpha-induced IkappaB kinase (IKK) activation and IkappaBalpha degradation were enhanced in TRAF6-deficient MEFs. Also, TNFalpha-induced DNA binding activity and transcriptional activation of nuclear factor kappaB (NF-kappaB) were also augmented in TRAF6-deficient MEFs. On the other hand, TRAF6 deficiency did not affect the TNFalpha-induced activation of mitogen-activated protein (MAP) kinases, ERK, JNK, and p38. Moreover, the reintroduction of exogenous TRAF6 into TRAF6-deficient MEFs clearly suppressed TNFalpha-induced IKK activation, NF-kappaB activation and subsequent cytokine expression. In contrast, both the deletion mutant (DeltaN) and the point mutant (C70A) of TRAF6, which is defective in its ubiquitin ligase activity, failed to repress TNFalpha-induced IKK activation, NF-kappaB activation and cytokine production. Thus, these data suggest that TRAF6 negatively regulates TNFalpha-induced NF-kappaB activation through its ubiquitin ligase activity.

Celecoxib potently inhibits TNFalpha-induced nuclear translocation and activation of NF-kappaB.

Celecoxib is a specific inhibitor of cyclooxygenase 2 (COX2). While it has been used for the treatment of chronic inflammatory conditions, including rheumatoid arthritis, its detailed anti-inflammatory mechanism has not been clarified. Here, we found that Celecoxib potently inhibited TNFalpha-induced transcriptional activity and DNA binding activity of NF-kappaB; however, Celecoxib had no effect on TNFalpha-induced IKK activation and degradation of IkappaBalpha and IkappaBbeta, suggesting that it inhibited NF-kappaB activation via suppressing downstream of IKK activation and IkappaBs degradation. Interestingly, it was also found that Celecoxib abrogated TNFalpha-induced nuclear accumulation of the NF-kappaB p65 subunit. As a result, TNFalpha-induced expression of inflammatory cytokines, CXCL1/KC and CCL2/MCP-1, was clearly inhibited by Celecoxib. On the other hand, Celecoxib had no effect on the TNFalpha-induced nuclear translocation of c-jun and activation of ERK, JNK, p38 and Akt. Taken together, these data indicate that Celecoxib specifically inhibits TNFalpha-induced NF-kappaB activation at the level of its nuclear translocation. This negative regulation of NF-kappaB activation by Celecoxib might be an important mechanism leading to its anti-inflammatory activity.

Hyperthyroidism and the management of atrial fibrillation.

Atrial fibrillation is often induced in patients with hyperthyroidism and may trigger heart failure. Its prevalence and outcome were examined to obtain up-to-date information. Persistent atrial fibrillation was observed in approximately 1.7% of new hyperthyroid patients. It occurs more frequently in males (2.86%) than in females (1.36%), even though the number of male hyperthyroid patients is only one fifth of female patients. The rate increased with age, being 8% in the patients older than 70 years old. The initial treatment is to control the heart rate with routine pharmacologic therapy and to start antithyroid therapy as quickly as possible. Attempted cardioversion should be deferred until approximately the fourth month of maintaining a euthyroid state, because more than 56% of atrial fibrillation spontaneously reverts to sinus rhythm when the thyroid hormone levels start to decline. Elective cardioversion for those whose atrial fibrillation persists is highly effective and sinus rhythm maintenance rates were 56.7% and 47.6% at the 10th and the 14th year, respectively, even though the duration of atrial fibrillation prior to cardioversion was extremely long (35.0 +/- 29.0 months).