The association of Primary biliary cholangitis and Graves’ disease coupled with management challenges: a case report of a 36-year-old black Zambian female patient.

Abstract

The occurrence of other autoimmune conditions in primary biliary cholangitis (PBC) patients is documented in literature and thyroid disease is such an example. Such cases are however rarely seen in the African setting and particularly in Zambia. Here we report a case of a 36-year-old black Zambian female patient who was diagnosed with PBC in 2014 at the University Teaching Hospital(UTH), Lusaka, Zambia. She was lost to follow-up until November 2020 when she presented with a flare of PBC. During the flare the patient reported a 2-weeks history of pruritus, fatigue, passing dark urine and pale stools, coupled with progressive weight loss. Examination revealed moist skin, scleral jaundice, generalised scratch marks, wasting with a body mass index (BMI) of 15kg/m², a small goitre with a bruit heard over it and fine tremors. She did not have proptosis, finger clubbing or cervical lymphadenopathy or pretibial myxoedema. File review showed no prior goitre. Ultrasound of the neck confirmed the homogenous thyroid gland with increased vascularity. Blood tests revealed a suppressed thyroid stimulating hormone (TSH) (<0.005Uiu/ml) elevated free triiodothyronine (FT3) (10.9pmol/l) and elevated free thyroxine (FT4) (53.4pmol/l). TSH receptor antibodies were also elevated. The clinical features and blood tests led to the confirmation of Graves’ disease in a patient with PBC. Our patient was subsequently started on carbimazole, propranolol and continued ursodeoxycholic acid with great clinical response to treatment of both the PBC and Graves’ disease.

Our patient managed to gain weight within six months of commencement of Graves’ hyperthyroidism treatment, with her BMI improving to normal, at 22.6 Kg/m². One year into her treatment she developed agranulocytosis likely from the carbimazole which was subsequently stopped resulting in her thyroid hormones going up again. The patient could not take propylthiouracil (PTU) in view of the liver disease as such radio-active iodine (which is not readily available) was the only feasible option.

Our case report contributes to the body of knowledge that PBC tends to coexist with autoimmune thyroid disease and should be looked out for with a high index of suspicion especially in patients with PBC who report weight loss despite doing well on PBC therapy.  We also seek to highlight the challenges in management and follow up of such patients in low resource setting. Although PBC is not so common in Black Africans, it should be suspected in patients who present with cholestatic jaundice especially in young female patients.