The prevalence of thyroid-associated ophthalmopathy (TAO) has been reported to be lower in several Asian populations than in Caucasians. The risk factors for TAO that have been demonstrated in Caucasians have not been studied in Asian populations. The aim of this study, therefore, was to determine the prevalence, risk factors, and clinical features of TAO in a cohort of multiethnic Malaysian patients with Graves' disease (GD).
The authors describe a case of a 37-year-old Malay lady with an unusually slow carbamazepine clearance, which may be related to genetic polymorphisms of drug metabolizing enzymes and transporters. When given a small daily dose of 200 mg immediate-release carbamazepine, this patient experienced drowsiness. Subsequently, she reduced her carbamazepine dose to 200 mg twice a week (on Mondays and Fridays), resulting in poor seizure control. At the same time, the patient was diagnosed with hyperthyroidism and was given carbimazole and propranolol. Hyperthyroidism and the concurrent use of these antihyperthyroid agents may have further slowed down the metabolism of carbamazepine. Therapeutic drug monitoring of carbamazepine was carried out, and a slow carbamazepine clearance of 1.45 L·h⁻¹ per 70 kg was observed. Genotyping of selected genetic variants in CYP3A4, CYP3A5, EPHX1, ABCB1, and ABCC2 revealed that she has CYP3A5*3/*3 and ABCB1 3435-CC genotypes. Both genotypes have been shown to be associated with higher adjusted mean serum carbamazepine concentration in Chinese and Korean patients with epilepsy. Physicians should be vigilant about the risk of adverse effects among patients with a slow carbamazepine clearance, especially in Malays. Simulations of carbamazepine dosing regimen based on the pharmacokinetic parameters of this patient were performed to allow individualization of drug therapy.
α°-thalassemia is a well-known cause of hydrops fetalis in South-East Asia and can be detected in utero. We report a very rare case of thyrotoxic cardiomyopathy associated with hyperplacentosis secondary to α°-thalassemia-associated hydrops fetalis. A 22-year-old primigravida with microcytic anemia presented at 27 weeks' gestation with pre-eclampsia, hyperthyroidism and cardiac failure. Serum β-human chorionic gonadotrophin was markedly elevated and abdominal ultrasound revealed severe hydropic features and enlarged placenta. Serum β-human chorionic gonadotrophin, cardiac function and thyroid function tests normalized after she delivered a macerated stillbirth. Histopathology of the placenta showed hyperplacentosis. Blood DNA analysis revealed that both patient and husband have the α°-thalassemia trait. This case illustrates a very atypical presentation of α°-thalassemia-associated hydrops fetalis and the importance of early prenatal diagnosis of α-thalassemia in women of relevant ethnic origin with microcytic anemia so that appropriate genetic counseling can be provided to reduce maternal morbidity and the incidence of hydrops fetalis.
A patient is said to have subclinical hyperthyroidism if he has a depressed thyroid stimulating hormone (TSH) level but is clinically euthyroid and has a normal thyroxine (T4) and triiodothyronine (T3) level. The aetiology of this condition is unknown, its progression is uncertain and the value of treatment is doubtful. These 2 cases show a rapid reversal of TSH suppression within a week after thyroidectomy. This suggest an unidentified potent but innocuous suppressor of TSH is produced by some large nodular goitres. Patients with multinodular goitres with subclinical hyperthyroidism can have their anxiety allayed with assurance that their condition is benign and that their TSH suppression is due to the presence of an innocuous substance which is protective in nature. This substance, when isolated, will find a useful place in the prevention and treatment of papillary carcinoma of the thyroid because of its potent effect on the pituitary-thyroid axis without causing any peripheral effects.
Pancytopenia can rarely complicate Grave's disease. It can be due to uncontrolled thyrotoxicosis or as a result of rare side effect of antithyroid medication. Pernicious anemia leading to Vitamin B12 deficiency is another rare associated cause. We report a case of a patient with Grave's disease and undiagnosed pernicious anemia whom was assumed to have antithyroid drug induced pancytopenia. Failure to recognize this rare association of pernicious anemia as a cause of pancytopenia had resulted in delay in treatment and neurological complication in our patient.
Optic neuropathy, an uncommon manifestation occurs in 5% of patients with Graves' ophthalmopathy. Its outcome is good if early and proper treatment given. We reported a 49 years old male patient of Graves' disease with bilateral optic neuropathy. He underwent bilateral transnasal endoscopic orbital decompression with marked improvement of visual acuity bilaterally. The preoperative visual acuity was 6/36 in his right eye and 6/60 in his left eye. Two days after operation, his visual acuity was 6/12 in his right eye and 6/24 in his left eye. Transnasal endoscopic orbital decompression is a choice of treatment in optic neuropathy in thyroid ophthalmopathy after trial of corticosteroids.
We report a male patient of Graves' Disease with bilateral exophthalmos who had undergone bilateral transnasal endoscopic orbital decompression with subsequent improvement of 3 mm in orbital proptosis bilaterally without any complications. Transnasal endoscopic orbital decompression is recommended as an alternative to traditional decompression techniques especially for purely cosmetic reasons.
Many neurological diseases like myopathy, periodic paralysis, ophthalmoplegia, and myasthenia gravis are known associations of thyrotoxicosis. However the association of neuropathy with thyrotoxicosis is not frequently recognized. First described by Charcot in 1889, thyrotoxic neuropathy or 'Basedow's Paraplegia' is a rarely reported entity. We describe here a case of a young woman with subacute distal neuropathy as the presenting manifestation of thyrotoxicosis. The neuropathy improved on antithyroid treatment. A careful literature search leads us to believe that peripheral neuropathy in thyrotoxicosis is under recognised. Thyroid function tests can be helpful in the diagnosis of this treatable neuropathy and should be included in the routine work up.
Thyrotoxicosis due to Graves disease is a relatively common endocrine disorder. The occurrence of a prolactinoma with co-secretion of growth hormone (GH) is on the other hand, rare. We report the rare co-existence of Graves' disease in a patient with macroprolactinoma and GH hypersecretion and describe the successful response to medical therapy with dopamine agonist and antithyroid therapy. We hypothesize that hyperprolactinaemia played a role in promoting autoimmune thyroid disease in our patient and that treatment of hyperprolactinaemia may have been important in suppressing autoimmune disease activity in Graves' disease. This case also reflects on the close and complex interactions between thyroid hormones, prolactin (PRL), GH and testosterone (T).
The effect of L-asparaginase on the thyroid gland has not been well documented. We report the first two cases of hyperthyroidism associated with thyroid nodule following L-asparaginase therapy for acute lymphoblastic leukemia (ALL). The thyroid function abnormalities were not severe, short-lived and did not require specific therapy.
Carbimazole, in 3 divided daily doses, is commonly prescribed for the treatment of thyrotoxicosis. However, based on its long intra-thyroid half-life, the drug may be effective when used as a single or twice daily dose. This study was undertaken to determine the effect of once, twice or thrice daily doses of carbimazole on thyroid function in patients with thyrotoxicosis. Seventy previously untreated thyrotoxic patients were randomly allocated to receive carbimazole 30 mg once (group 1), 15 mg twice (group 2) and 10 mg thrice (group 3) daily. All patients were also prescribed propranolol 20 mg thrice daily for the first 4 weeks. Blood was taken for total T3, T4, TSH, blood counts and liver enzymes determinations at the beginning and at 6 weeks of treatment. Only 48 (68.6%) patients were included in the analysis, as the rest defaulted follow-up (20.0%) or blood samples were not available at review (11.4%). Of the 48 patients, 17 were in group 1, 16 in group 2 and 15 in group 3. Following 6 weeks of treatment, there was no significant difference in the mean serum levels of total T3 and T4 between the 3 groups. However, there was a significant decrease in the mean serum levels of total T3 and T4 as compared to the start of the treatment. Four patients (23.5%) in group 1, 4 patients (25%) in group 2 and 3 patients (20%) in group 3 were still thyrotoxic at 6 weeks of treatment, whilst 10 patients (58.8%) in group 1, 6 patients (37.5%) in group 2 and 3 (20%) in group 3 were biochemically hypothyroid.(ABSTRACT TRUNCATED AT 250 WORDS)
A 25 year old female presented with hypothyroidism which was followed by the development of hyperthyroidism about 1 1/2 years later. This uncommon phenomenon is postulated to result from changes in the relative amounts of stimulatory and inhibitory TSH receptor antibodies. This case illustrates the possible continuum between Graves' disease and Hashimoto's thyroiditis within the broad spectrum of autoimmune thyroid disease.
Study site: Primary care clinic. University Malaya Medical Cengtre (UMMC), Kuala Lumpur, Malaysia
The presenting features of 236 thyrotoxic patients seen in the thyroid clinic were reviewed. 18.65% of these patterns had one or more dermatological complaints at presentation. There was no specific difference in this group of patients when compared with the general hyperthyroid population with regard to age, race, sex, duration of hyperthyroidism or biochemical indices of thyrotoxicosis. The two major complaints were itching and alopecia. The prevalence of pruritus at 6.4% in our series was identical to that of other workers, but we had a much lower occurrence of alopecia at 2.6%. The diagnosis of thyrotoxicosis was delayed in two patients in whom the only major complaint was pruritus. These symptoms cleared quickly when these patients became euthyroid. However there were other patients who noted hair loss with anti-thyroid medications. The incidence of vitiligo, eczema, onycholysis in our series was much lower those quoted in the Western literature The occurrence of pretibial myoxoedema in our series is similar to that of other workers from this region. The other miscellaneous manifestations include urticaria, xanthelasma and systemic lupus erythematosis. In conclusion we feel the cutaneous manifestations of hyperthyroidism are common in our patients.
We report a patient with unusual manifestations of hyperthyroidism which initially suggested lymphoma. The pathophysiology of these features in thyrotoxicosis is discussed. The need to consider thyrotoxicosis in an otherwise unexplained case of lymphoid hyperplasia will be stressed.
The serum alpha-1 acid glycoprotein of 9 euthyroid subjects, 14 hypothyroid patients and 21 hyperthyroid patients was determined by radial immunodiffussion in agar plates. The serum alpha1 acid glycoprotein level in both the hypothyroid and hyperthyroid patients were significantly lowered when compared to the euthyroid subjects. There was no significant correlation between the alpha-1 acid glycoprotein level mid the Liothyronine resin uptake (T3 resin. uptake) and the serum total Thyroxine Iodide (T4I) level.
Thyrotoxic psychosis is an uncommon phenomenon and the presentation is usually of the affective disorders. Three cases manifesting psychotic symptoms akin to schizophrenia are described. The neurobiocheinistry and treatment are discussed.
This report deals with the problems of a young man who was clinically euthyroid but biochemically hyperthyroid. The possibility of peripheral resistance to thyroid hormones to explain this paradoxical state is discussed. The importance of recognising this condition to avoid the erroneous diagnosis of thyrotoxicosis and inappropriate therapy is stressed.
A total of 23 patients with psychoses associated with thyrotoxicosis were admitted to the psychiatric unit of a University Hospital over a 13-year period, of which 20 patients were included in this retrospective study. It was found that a parallel relationship between thyrotoxicosis and psychosis appears to exist in six patients, while in the remaining 14 patients, the course of the two disease processes were largely independent of each other. Paranoid delusions and auditory hallucinations were the most prominent psychiatric symptoms. Depression was commonly seen even in patients who were not having an affective illness. In four patients, a mixed schizo-affective psychosis was seen, suggesting that the diagnostic distinction between the affective and schizophrenic reactions are often blurred in psychosis associated with thyrotoxicosis.
This report deals with a middle aged man in whom the presenting symptom of the disorder was dysphagia. The clinical approach to the final diagnosis of thyrotoxic myopathy causing dysphagia is outlined and the pathophysiology of dysphagia then discussed. The need to include thyrotoxicosis in the differential diagnosis of an otherwise unexplained case of dysphagia is stressed.