Validity of serum CK activity in the diagnosis of thyroid dysfunction

This study assessed the pattern of changes in serum creatine kinase [CK] activity in [100] patients with a variety of clinical manifestations of either increased or decreased thyroid function and evaluated the validity of such changes in the diagnosis of both conditions They were biochemically assessed for thyroid function and compared with a control group of 67 apparently healthy subjects According to thyroid function tests, the subjects were classified into 3 groups Group 1 Hypothyroid patients [n=50], which was divided into 2 subgroups Group A[Overt hypothyroidism] It included 43 patients with TT4 60 nmol/l. The second group [Group 2] included 50 hyperthyroid patients, while [Group 3] was composed of 67 euthyroid subjects. Serum CK activity was noticeably elevated in hypothyroid patients compared to both normal and hyperthyroid subjects [mean +SD was 204.10 + 97.72 Vs 79.97+ 26.35 and 79.36 + 26.88 u/L respectively]. There was no significant difference in the mean serum CK activity between group A and B [Z =87, P>0.05] A significant positive correlation was revealed between serum TSH and CK in hypothyroid patients [Group I] where [r=0.35, P<0.01], while there was no such significant association in either group A or B [p>O.O5],and thus did the hyperthyroid patients [r= -0.22, P>0.05]. For patients in group1, the sensitivity, specificity, positive predictive value [PPV], negative predictive value [NPV], accuracy rate, positive likelihood ratio [PLR] and negative likelihood ratio [NLR] of elevated serum CK activity as a diagnostic test were 74%, 95.5%, 92.5%, 87%, 86%, 16.40, 0.27 respectively. However, they were 0%, 95.5%, 0%, 56%, 5.4%, 0 and 0.96 respectively for the diagnosis of hyperthyroidism. In conclusion high serum CK activity is a fairly sensitive and highly specific test for the diagnosis of hypothyroidism with a high PPV value mainly for overt [uncompensated] cases. This study indicates that the determination of CK might be a useful screening tool for hypothyroidism

Reference range of serum fructosamine in population of Ninevah province

Diabetes mellitus [DM] is a common health problem. Assessment of diabetic control requires regular monitoring of glycaemic state by measuring plasma glucose and glycated protein [including serum fructosamine] at regular periods. To determine the reference range for measured and corrected serum fructosamine [FAm and FAc] in adult population of Ninevah Province in Northern Iraq. This study represents a part of cross sectional survey of DM in Ninevah Province in Northern Iraq. Fasting plasma glucose [FPG] and serum fructosamine [FA] were compared in 1015 subjects aged >/= 25 years from different urban and rural areas in Ninevah Province. The subjects were classified into 3 groups: Non-diabetics [n= 910], diabetics [n= 92], and those with impaired glucose tolerance [IGT] [n= 13]. The distribution of FAm and FAc values among the non-diabetics showed a Gaussian pattern. No significant correlation was observed between serum FAm and albumin and FAm in non-diabetics [r= 0.14, p> 0.05] and diabetics [r= 0.08, p>0.05]. A highly significant correlation was also observed between FAm and FAc in both non-diabetics [r= 0.90, p< 0.0001] and diabetics [r= 0.97, p< 0.0001]. The reference range [normal range] for both FAm and FAc were calculated as mean +/- 2SD owing to the normal pattern of distribution. For FAm; it was 1.30-2.65 mmol/l and for FAc; it was 1.18-2.60 mmol/l. Elderly non- diabetics exhibited higher FA values than younger subjects. No sex difference was noted when FAm values were corrected according to serum albumin. It can be concluded that studies conducted in different parts of the world, including the current study, had exhibited different reference ranges for serum FA. It is recommended to establish local reference ranges whenever fructosamine test is used