Introduction: While hypertension is extremely common in adults, genetic hypertension syndromes with onset in childhood are uncommon and likely underrecognized, presenting a unique challenge for healthcare providers. 

Case Presentation: An otherwise healthy 7-year-old male was noted to have elevated blood pressures (BP) associated with headaches. Labs including basic metabolic panel, thyroid stimulating hormone, serum renin, 24-hour urine catecholamines, and urinalysis were normal. Renal ultrasound with doppler revealed normal renal structure and function without renal artery stenosis. 2D echocardiogram demonstrated appropriate cardiac function and anatomy without hypertrophy. On ambulatory blood pressure monitoring, maximum BP was 157/107 with average BP of 139/81. His hypertension persisted despite a low salt diet, so Lisinopril was initiated. As the patient aged, his hypertension persisted, and he developed short stature (height 3.7th percentile). He had short, thick fingers and toes on exam consistent with brachydactyly. Hand and feet x-rays were declined per family choice. On further questioning, there was a significant family history of early onset hypertension associated with suspected brachydactyly. His father and half-sister, also with short stature and short, thick digits, were diagnosed with high BP and started on anti-hypertensives as teenagers but had never been diagnosed with a secondary hypertension syndrome. 

Final/Working Diagnosis: Hypertension and brachydactyly syndrome (HTNB) is an autosomal dominant genetic cause of hypertension that is associated with short stature and a form of brachydactyly manifested by shortening of both phalanges and metacarpals. It is a severe salt-independent but age-dependent condition that, if left untreated, can result in death from stroke before age 50. Prevalence is estimated at less than 1 in 1,000,000, making recognition particularly difficult. In this case, the patient’s brachydactyly and short stature allowed for identification of HTNB within himself and his family.

Management/Outcome/Follow-Up: This case demonstrates the utility of recognizing phenotypic features of genetic hypertensive syndromes to aid in early diagnosis, treatment, 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.

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