|LETTER TO EDITOR
|Ahead of print publication
Prevalence of thyroid dysfunction in patients with systemic lupus erythematosus: A descriptive cross-sectional study
Mahmood Dhahir Al-Mendalawi
Department of Paediatrics, Al-Kindy College of Medicine, University of Baghdad, Baghdad, Iraq
Mahmood Dhahir Al-Mendalawi,
Mahmood Dhahir Al-Mendalawi, P. O. Box 55302, Baghdad Post Office, Baghdad
Source of Support: None, Conflict of Interest: None
In April–June 2020 issue of the Indian Journal of Rheumatology, Desai et al. reported that thyroid dysfunction was observed in 42% of Indian patients with systemic lupus erythematosus (SLE). Hypothyroidism was the predominant dysfunction in the forms of clinical hypothyroidism (71%) and subclinical hypothyroidism (29%). None of the SLE patients had hyperthyroidism. In addition to the few study limitations mentioned by Desai et al. I presume that the following limitation ought to be taken into consideration. It is worthy to mention that normative data (ND) of thyroid function tests (TFT) are usually utilized to assess thyroid health status. Since variations do exist between local and international ND of TFT, population-specific ND has been generated. Interestingly, India has already set its own ND of TFT to be utilized clinically and in academic researches. The overall triiodothyronine and thyroxin (T4) values in the Indian population, regardless of age, was reported to be ranged from 2.4 to 8.8 (mean 4.6 ± 0.9) pmol/L and 10.1–24.8 (mean 15.40 ± 2.0) pmol/L, respectively, while the mean thyroid-stimulating hormone (TSH) value was 2.2 ± 0.9 mIU/L. In the study methodology, Desai et al. mentioned that they employed the standard definitions to interpret readings of various components of TFT and diagnose thyroid disorders. The employed definitions involved overt hypothyroidism as TSH levels >10 lU/L and subclinical hypothyroidism as elevated TSH (5–10 lU/L) with normal (T4 10–28 pmol/l) as per the laboratory cutoffs. I wonder why Desai et al. did not refer to that national ND of TFT instead of the foreign standard in the study methodology. I presume that employing national standards could address more accurate results on the prevalence and forms of thyroid diseases in SLE patients.
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| References|| |
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