Abstract P388: Thumbs Down: A Rare Familial Cause Of Hypertension Associated With Brachydactyly

Abstract

While hypertension (HTN) is extremely common in adults, genetic HTN syndromes with onset in childhood are much less common and present a unique challenge for healthcare providers. Many of these syndromes are rare and children are only screened annually for HTN, leading to delayed initiation of antihypertensives. We present a case of an otherwise healthy 7-year-old male who was noted to have persistently elevated blood pressures (BP) associated with headaches. Echocardiogram revealed normal cardiac function and anatomy without hypertrophy. Basic metabolic panel, urinalysis, and renal ultrasound revealed normal renal structure and function with no evidence of renal artery stenosis on Doppler. Additional negative workup included a thyroid function panel, serum renin, and 24-hour urine catecholamines. On ambulatory blood pressure monitoring, maximum BP was 157/107 with average BP of 139/81. His HTN did not respond to a low salt diet, so lisinopril was initiated. As the patient aged, his HTN persisted despite appropriate medical therapy and he developed short stature (height 3.7 th percentile). He had short, thick fingers and toes on exam consistent with brachydactyly. On further questioning, there was a family history of pediatric onset HTN associated with suspected brachydactyly in his paternal grandfather, father, and paternal half-sister, however no family members had received a formal diagnosis. He was ultimately diagnosed with hypertension and brachydactyly syndrome (HTNB), a rare autosomal dominant disorder characterized by early onset severe HTN, short stature, brachydactyly, and increased risk of recurrent strokes under age 50. Incidence is unknown due to the rarity of reported cases, which makes screening and recognition more difficult. This case demonstrates the utility of recognizing phenotypic features of genetic hypertensive syndromes to aid in early diagnosis, resulting in reduced morbidity/mortality and counseling for family members. Blood pressure screening including ambulatory blood pressure monitoring should be considered in any patient with brachydactyly and/or short stature, even if phenotypic features are mild. Anti-hypertensive medication should be initiated early given the untreated clinical course of this disease.