Endocrine Abstracts

Introduction: Hematologic abnormalities are frequently observed during hyperthyroidism and are related to complex multifactorial pathogenic mechanisms that are still poorly understood and may affect the three hematopoietic lineages in isolation or in combination. These abnormalities are exceptionally revealing and are usually subclinical. For the endocrinologist, they raise the problem of the risk of their aggravation under the hematotoxic effect of synthetic antithyroid drugs (ATS). However, certain abnormalities such as leuko-neutropenia are sometimes simply the expression of a physiological phenomenon of margination of white blood cells which falsely underestimates the count of this lineage and which must be detected.

Observation: Patient aged 45 years, followed for hyperthyroidism on Graves’ disease initially put on CTC 60 mg with adjuvant treatment, presented a cardiac complication such as of an AFib put on Sintrom and b-blockers, with a past history of angina put, diabetic since 5 years on insulin, at the clinical examination, patient in good general condition, FC: 89 bpm, homogeneous grade 2 goiter without palpable nodul with bilateral inactive exophthalmos, the biological test objectified a TSHus: 0. 001 μIU/ml, T4L: 48.4 pg/ml (6-12), T3L: 13.2 pg/ml (2.6-5.7), TRAK: 19. 8 IU/l, associated with haematological disturbances such as neutropenia controlled on several occasions: WBC: 5320/mm3, PNN: 850/mm3, before the start of the antithyroid treatment, a control of the blood count formula after 2 h of physical activity, objectified a re-ascension to normal PNN levels at 2780/mm3. This was in fact a physiological margination of the PNN on the blood vessel wall, which was unmasked by the effort, a situation aggravated by the hyperthyroidism but which did not contraindicate the introduction of synthetic antithyroid.

Conclusion: Faced with the coexistence of hyperthyroidism and leukocyte lineage disturbances, a simple stress test should be rapidly performed to unmask false neutropenia, thus avoiding unnecessary transfer to the hospital.