= LIPOCALCINOGRANULOMATOSIS = TEUTSCHLÄNDER DISEASE

= rare familial metabolic disorder characterized by solitary or multiple painless, periarticular masses

= disease with progressive large nodular juxtaarticular calcified soft-tissue masses in patients with normal serum calcium and phosphorus + NO evidence of renal, metabolic, or collagen-vascular disease

Etiology: autosomal dominant (⅓) with variable clinical expressivity; unknown biochemical defect of phosphorus metabolism → abnormal phosphate reabsorption + 1,25-dihydroxy-vitamin D formation

Path: multilocular cystic lesions with creamy white fluid (calcium hydroxyapatite crystals with amorphous calcium carbonate and calcium phosphate) + many giant cells (granulomatous foreign body reaction) surrounded by fibrous capsule

Associated with: hyperostosis, diaphysitis, pseudoxanthoma elasticum

Age: onset mostly within 1^st / 2^nd decade (range of 1–79 years); M÷F = 1÷1; predominantly in Blacks

• progressive painful / painless soft-tissue mass with overlying skin ulceration + sinus tract draining chalky milklike fluid
• prominent dental abnormalities
• swelling; limitation of motion
• hyperphosphatemia + ↓ fractional phosphate excretion
• hypervitaminosis D (↑ 1,25-dihydroxy–vitamin D formation)
• normal serum calcium, alkaline phosphatase, renal function, parathyroid hormone
• Soft tissue
  Location: hip (greater trochanteric bursa) >elbow >shoulder >foot, rib, ischial spine, wrist; single / multiple joints; ALMOST NEVER knees
  Distribution: periarticular; usually along extensor surface of joints (? initially a calcific bursitis)
  X-ray:
  • amorphous cystic multilobulated homogeneously calcified soft-tissue mass of 1–20 cm in size
  • underlying bones NORMAL without erosion / osseous destruction
  • periosteal reaction ← bone marrow involvement
  
  CT:
  • patchy areas of increased attenuation
  • cystic appearance with radiolucent septa (= connective tissue)
  • “sedimentation” sign = fluid-fluid levels with milk-of-calcium consistency
  
  NUC:
  • ↑tracer uptake of soft-tissue mass on bone scan
  
  MR:
  • inhomogeneous high SI on T2WI (in spite of large amount of calcium) of 2 distinctive patterns:
    • diffuse lower-signal-intensity pattern
    • bright nodular pattern with alternating areas of high signal intensity and signal void
  • inhomogeneous lesion with low SI on T1WI
• Bone
  • diaphyseal periosteal reaction (diaphysitis)
  • patchy areas of calcification in medullary cavity (= calcific myelitis)
  • increased uptake on bone scintigraphy
• Teeth
  • bulbous root enlargement
  • pulp stones = intrapulp calcifications
• Pseudoxanthoma elasticum-like features
  • calcinosis cutis = skin calcifications
  • vascular calcifications
  • angioid streaks of retina
• Eye
  • angioid streaks / corneal calcification deposits

Prognosis: tendency for recurrence after incomplete excision

Rx: phosphate depletion

DDx: Chronic renal failure on hemodialysis, calcinosis universalis, calcinosis circumscripta, calcific tendonitis, CPPD, paraosteoarthropathy, hyperparathyroidism