HISTOPATHOLOGICAL PATTERN OF THYROID DISEASES AS SEEN IN AHMADU BELLO UNIVERSITY TEACHING HOSPITAL, ZARIA: A TEN YEAR REVIEW (2005-2014)

Abstract

Background
In the last several years, studies on thyroid diseases in the northern part of Nigeria focused
mainly on neoplastic lesions. This index study aimed to analyse all histological types of thyroid
diseases and their frequency distribution patterns in Zaria, north west Nigeria and to compare our
findings with similar works in Nigeria and globally.
Materials and method
All thyroid biopsies and specimens received in the department of Pathology, Ahmadu Bello
University Teaching Hospital Zaria over a ten year period (2005-2014) were analysed. The
patients’ case cards and H&E stained slides were retrieved and reviewed with supervising
consultants. Fresh sections were cut and stained where necessary. The cases were grouped into
developmental/congenital, goitre/hyperplastic lesions, inflammatory and autoimmune diseases.
The neoplastic lesions were classified using the World Health Organization (WHO)
classification of thyroid tumours. Statistical program for Social Sciences (SPSS) version -20.0
software was used for data analysis. Data was presented as simple frequency tables, figures and
photomicrographs.
Results
There were 302 thyroid diseases diagnosed during the study period. Only 297 cases fulfilled the
study inclusion criteria and of these, 7 cases’ initial diagnoses were reviewed. There were 255
females and 42 males with M: F ratio 1:6. The histological types of diseases included goitre 214
(72.1%) with simple colloid goitre accounting for 190 (64.0%) cases and multinodular goitre for
xii

24 (8.1%) cases. Graves disease and Hashimoto thyroiditis accounted for 12(4.0%) and 3(1.0%)
cases respectively while lymphocytic thyroiditis accounted for 1(0.3%) case. There were 36
(12.1%) adenoma cases and 14 (4.7%) carcinomas. The adenoma cases included follicular
adenoma, Hurthle cell adenoma and trabecular adenoma. Papillary carcinoma was the
commonest (71.4%) thyroid cancer followed by follicular carcinoma (14.3%). One case each of
medullary carcinoma (7.1%), and undifferentiated carcinoma (7.1%) were also seen.
Thyroglossal cysts accounted for 17 (5.7%) cases and were predominant in children aged below
10years.
Conclusion
This study showed that thyroid diseases in Zaria had a female predominance with peak age
frequency between 30 – 50yrs of age. The commonest diseases were colloid goitre, follicular
adenoma and papillary carcinoma. These findings are comparable with several studies on thyroid
diseases in Nigeria and globally.