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Age / Sex : 19 / M
Age / Sex : 13 month / Female
Chief complaint : Limping Labaratory finding
: –
ALP : 1107 IU/L
(normal: 60-300 IU/L) –
Calcium : 9.1
mg/dL (normal: 8.6-10.0 mg/dl) –
Phosphorus : 2.7
mg/dL (normal: 2.7-4.5 mg/dl) –
PTH : 269 pg/ml
(normal: 9-55 pg/ml)
1) What is your impression?
Two weeks later, you can see the final diagnosis with a brief discussion of
this case.
* Send Application Answers to In Sook Lee, MD ([email protected])
Courtesy : So-yeon, Lee,
Kangbuk Samsung Hospital,
Sungkyunkwan University School of Medicine
Diagnosis: Rickets, Vitamin D deficiency
Discussion
Findings: Radiographs
of both hands and both lower extremities revealed absence of the radiopaque
fine line along physis representing the zone of provisional calcification. The
physeal surfaces show cupping, fraying and irregularity. There is bowing of
tibial shafts.
Diagnosis: Rickets,
Vitamin D deficiency
Discussion: Rickets
is a group of diseases of infants and children caused by an insufficiency of
vitamin D. The major effect of vitamin D is to increase absorption of calcium
and phosphorus from the intestinal tract. In the skeleton, major roles of
vitamin D are the mobilization of calcium and phosphorus from previously formed
bone and the promotion of maturation and mineralization of the organic matrix.
Deficiencies and diseases of vitamin D metabolism cause poor mineralization of
oteoid and the arrest of new bone formation. When this happens in a bone already
formed, it results in a condition of osteomalacia. During childhood,
insufficiency of vitamin D causes a failure of the growth and alteration of the
epiphyseal complex including metaphysis, physis and epiphysis. This form of
osteomalacia is known as rickets.
The radiologic
findings of rickets often precede the clinical manifestations. The classic radiologic
findings of rickets occurs at the metaphyses of the most rapidly growing bones.
Failure to transform growing cartilage into mineralized cartilage and osteoid
results in cupping, fraying and irregularity of the physeal surface. Failure of
mineralization of the zone of provisional calcification results in loss of the
Laval-Jeantet ring – the straight area at the metaphyseal margins in infrants.
There is loss of normal cortical distinction as results of secondary
hyperparathyroidism. There are loss of definition of the margins of the epiphyses
and longitudinal widening of the physis. There may be small ossification
center. There often is bowing of the femoral and tibial shafts. Frayed and
widened anterior rib ends are often present on chest radiographs.
References:
1. Mankin HJ. Rickets, osteomalacia, and renal
osteodystrophy. Orthop Clin North Am 1990;21:81-96
2. Rosenberg AE. The pathology of metabolic bone disease.
Radiol Clin North Am 1991;29:19-36
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