INTRODUCTIONSubclinical hyperthyroidism (SH, grade 1, thyrotropin (TSH) ≥0.1 mU/L and grade 2, TSH <0.1 mU/L) is a common disorder with increased prevalence in older subjects. There is evidence for increased morbidities in SH, such as atrial fibrillation and osteoporosis. We aim to study the natural history and comorbidities of SH from patients referred to a tertiary endocrine clinic in Singapore as they are currently unknown.

MATERIALS AND METHODSRetrospective evaluation of SH subjects for natural progression and comorbidities.

RESULTSOne hundred and thirteen SH subjects (male/female: 24/89, mean age: 67.2 years, grade 1/grade 2: 60/53) were identified from the endocrine clinic. The aetiology of SH include 52 multinodular goitre, 15 Graves' disease, 7 toxic adenoma and 39 unclassified. A minority of SH patients (5.3 %) progressed to overt hyperthyroidism while 13% remitted to euthyroid state (1 to 3 years with a mean follow-up of 18 months) in the total cohort. Most of the patients remained in SH state during follow-up (50/60 in grade 1 SH and 42/53 in grade SH). However, no single predictive factor could be identified for progression or remission of SH. The prevalence of morbidities in SH subjects include ischaemic heart disease (16.8%), heart failure (8.9%), tachyarrhythmias (13.3%), any cardiovascular disease (28%), cerebrovascular disease (28%), osteoporosis (28%), and any fracture (15.9%).

CONCLUSIONMost of SH cases in our cohort remain in subclinical state with very few progressing to overt hyperthyroidism. Significant proportion of SH subjects have vascular disease, but this association needs to be confirmed in prospective controlled studies.

Aged ; Disease Progression ; Female ; Humans ; Hyperthyroidism ; complications ; diagnosis ; Male ; Prospective Studies ; Tertiary Care Centers

BACKGROUNDMuch is known about the cytogenetic lesions that characterize multiple myeloma (MM) patients from the USA, Europe, and East Asia. However, little has been published about the disease among Southeast Asians. The aim of this study was to determine the chromosomal abnormalities of MM patients in our Singapore population.

METHODSForty-five newly-diagnosed, morphologically confirmed patients comprising 18 males and 27 females, aged 46 - 84 years (median 65 years) were investigated by karyotyping and fluorescence in situ hybridization (FISH). FISH employing standard panel probes and 1p36/1q21 and 6q21/15q22 probes was performed on diagnostic bone marrow samples.

RESULTSThirty-four cases (75.6%) had karyotypic abnormalities. Including FISH, a total detection rate of 91.1% was attained. Numerical and complex structural aberrations were common to both hyperdiploid and non-hyperdiploid patients. Numerical gains of several recurring chromosomes were frequent among hyperdiploid patients while structural rearrangements of several chromosomes including 8q24.1 and 14q32 characterized non-hyperdiploid patients. With FISH, immunoglobulin heavy chain (IGH) gene rearrangements, especially fibroblast growth factor receptor 3 (FGFR3)/IGH and RB1 deletion/monosomy 13 were the most common abnormalities (43.4%). Amplification 1q21 was 10 times more frequent (42.5%) than del(1p36) and del(6q21).

CONCLUSIONSWe have successfully reported the comprehensive cytogenetic profiling of a cohort of newly-diagnosed myeloma patients in our population. This study indicates that the genetic and cytogenetic abnormalities, and their frequencies, in our study group are generally similar to other populations.

Aged ; Aged, 80 and over ; Chromosome Aberrations ; Cytogenetics ; Female ; Humans ; Immunoglobulin Heavy Chains ; In Situ Hybridization, Fluorescence ; Karyotyping ; Male ; Middle Aged ; Monosomy ; genetics ; Multiple Myeloma ; genetics ; pathology ; Receptor, Fibroblast Growth Factor, Type 3 ; genetics ; Retinoblastoma Protein ; genetics ; Singapore