Endocrine · Year 2 · from Endocrine

Case 1: Acromegaly

Patient Demographics

  • Age: 45 years
  • Sex: Male
  • Occupation: Software engineer

Chief Complaint

"My wedding ring doesn't fit anymore, and my shoes are two sizes bigger than they were five years ago."

History of Present Illness

A 45-year-old man presents to his primary care physician after noticing progressive changes in his appearance over the past several years. He reports that his hands and feet have enlarged, requiring larger gloves and shoes. His wife has commented that his facial features have become "coarser." He has developed excessive sweating, joint pain in his knees and hips, and has been told he snores loudly with episodes of apnea. He was recently diagnosed with type 2 diabetes and hypertension. Old photographs from 10 years ago show distinctly different facial features.

Physical Examination

  • Vital Signs: BP 152/94 mmHg, HR 78 bpm
  • General: Large, prominent facial features; enlarged hands and feet
  • HEENT: Frontal bossing, prognathism (jaw protrusion), macroglossia, widely spaced teeth, thickened lips and nose
  • Cardiovascular: S4 gallop present
  • Extremities: Soft tissue swelling of hands and feet, doughy feel to skin
  • Skin: Oily, skin tags present
  • Neurologic: Bilateral carpal tunnel syndrome symptoms

Workup

  • Laboratory Studies:
  • IGF-1: 856 ng/mL (markedly elevated for age, normal 75-216)
  • Random GH: 18 ng/mL (elevated, normal <1 ng/mL)
  • Oral Glucose Tolerance Test (OGTT): GH nadir 8.2 ng/mL (fails to suppress below 1 ng/mL)
  • Prolactin: 42 ng/mL (mildly elevated - co-secretion or stalk effect)
  • Fasting glucose: 142 mg/dL
  • HbA1c: 7.2%
  • MRI Pituitary with Contrast: 1.8 cm pituitary macroadenoma

Diagnosis

Acromegaly due to GH-secreting pituitary adenoma (somatotroph adenoma)

Treatment

  1. First-line: Transsphenoidal surgical resection
  2. If not cured surgically:
  • Somatostatin analogs (octreotide LAR, lanreotide)
  • GH receptor antagonist (pegvisomant)
  • Dopamine agonist (cabergoline) - especially if prolactin co-secretion
  1. Radiation therapy for refractory cases
  2. Management of comorbidities: Diabetes, hypertension, sleep apnea
  3. Colonoscopy screening (increased risk of colon polyps/cancer)

Clinical Pearl

The diagnosis of acromegaly is often delayed 7-10 years from symptom onset because changes are gradual and insidious. IGF-1 is the best screening test as it reflects integrated GH secretion over 24 hours. Confirmation requires demonstrating failure of GH suppression during an oral glucose tolerance test (GH should normally suppress to <1 ng/mL). Mortality in acromegaly is primarily due to cardiovascular disease, with patients having a 2-3 fold increased risk of death if GH/IGF-1 levels are not controlled.

Clinical Image

Comparison photographs showing progressive coarsening of facial features in acromegaly over years, with frontal bossing, prognathism, and soft tissue enlargement.

Image Source: Wikimedia Commons - "Acromegaly facial features" License: CC BY-SA 3.0 URL: https://commons.wikimedia.org/wiki/File:Acromegaly_facial_features.JPEG

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