Osteocalcin, Serum
Medical Test

Overview

Osteocalcin is the major non-collagen calcium binding protein and it is excreted by osteoblasts in the bone. The serum concentrations are an indication of bone formation. The synthesis of osteocalcin is vitamin D independent. Elevated results are usually associated with increased bone turnover such as what is seen in osteoporosis. Bisphosphonated drugs used to treat osteoporosis can be monitored for effectiveness by measuring osteocalcin levels. Levels are normally high in childhood and then peak in early puberty. During menopause a second peak usually occurs in females.

Although results are not strictly diagnostic of osteoporosis, a decrease in the value can be interpreted as evidence of a favorable response to treatment. Patients that are on vitamin K antagonist medication can have unreliable results. Therefore, ELISA methodology is the best choice to test for undercarboxylated osteocalcin. This assay should be used in conjunction with other bone markers for best interpretation. Bone mineral densitometry and imaging studies are the gold standard for the evaluation of osteoporosis. Bone formation/ resorption may be accurately reflected in patients taking 1,25-dihydroxyvitamin D or if there is an abnormality with it.

Of note, bone formation and serum Osteocalcin level follows a diurnal rhythm and is also subject to the menstrual cycle. Variation by as much as 50% can be seen from a nocturnal peak to a morning low, with a 10% day to day variation, and as large as a 60% increase can be seen following a fracture.

Clinical Utility
  • As an aid in monitoring mineral and bone metabolism
  • Determine efficacy of therapy in osteoporosis and metastatic bone disease
  • Monitoring bone metabolic changes secondary to Cushing syndrome
  • Monitoring bone metabolic changes secondary to primary hyperparathyroidism
  • Monitoring bone metabolic changes secondary to malabsorption syndrome
  • As an aid in diagnosis of plasma cell myeloma
  • Selection of therapy for patients with hypercalciuria

Interpretation

Increased in:

  • Primary or secondary osteoporosis
  • Osteomalacia
  • Osteopenia due to vitamin D deficiency
  • Growth hormone deficiency
  • Hypogonadism
  • Paget’s disease
  • Osteoporosis
  • Cushing syndrome
  • Renal osteodystrophy
  • Inflammatory states such as rheumatoid arthritis
  • Bone metastasis
  • Hyperthyroidism
  • Primary Hyperparathyroidism
  • Myeloma
  • Hypercalciuria
  • Children
  • Long term corticosteroid use
  • Acromegaly
  • Recent bone fracture
  • Menopause
  • Lactation
  • Excercise
  • Incresed age

Decreased in:

  • Decreased results may indicate favorable therapeutic response
  • Pregnancy
  • Growth hormone deficiency
  • Hypothyroidism
  • Hypoparathyroidism
  • Liver disease
  • Alcoholism
  • Long term corticosteroid therapy
  • Obesity
  • Type 2 Diabetes

Reference Ranges
  ng/mL ug/L
Child 6-9.9 yr:  40.2-108  40.2-108
10-13.9 yr:  35.8-166  35.8-166
14-17.9 yr:    
M:  27.8-194  27.8-194
F:  16.3-68.7  16.3-68.7
Adult M:  11.3-35.4  11.3-35.4
F:  7.2-27.9  7.2-27.9
Adult M:  1.1-7.2  1.1-7.2
F, premenopausal:  0.5-7.0  0.5-7.0


 

 

Methodology

Enzyme Immunoassay (EIA), ELISA, RIA, IRMAs, ICMAs. Osteocalcin values vary widely between methods.

Specimen Collection

Serum

Serum Red top preferred, Serum gel(SST) acceptable.
Must be fasting.
Separate within 1 hr and freeze.

Additional Testing

Alkaline Phosphatase, Alkaline Phosphatase isoenzyme, Calcium Levels, Vitamin D, Parathyroid Hormone, Liver profile, Phosphorus.

CPT
83937$29.85

ICD10
ICD CODE AND DESCRIPTIONLCD CODENCD CODE
C40 - Malignant neoplasm of bone and articular cartilage of limbs——
C40.0 - Malignant neoplasm of scapula and long bones of upper limb——
C40.00 - Malignant neoplasm of scapula and long bones of unspecified upper limb——
C40.01 - Malignant neoplasm of scapula and long bones of right upper limb——
C40.02 - Malignant neoplasm of scapula and long bones of left upper limb——
C40.1 - Malignant neoplasm of short bones of upper limb——
C40.10 - Malignant neoplasm of short bones of unspecified upper limb——
C40.11 - Malignant neoplasm of short bones of right upper limb——
C40.12 - Malignant neoplasm of short bones of left upper limb——
C40.2 - Malignant neoplasm of long bones of lower limb——
C40.20 - Malignant neoplasm of long bones of unspecified lower limb——
C40.21 - Malignant neoplasm of long bones of right lower limb——
C40.22 - Malignant neoplasm of long bones of left lower limb——
C40.3 - Malignant neoplasm of short bones of lower limb——
C40.30 - Malignant neoplasm of short bones of unspecified lower limb——
C40.31 - Malignant neoplasm of short bones of right lower limb——
C40.32 - Malignant neoplasm of short bones of left lower limb——
C40.8 - Malignant neoplasm of overlapping sites of bone and articular cartilage of limb——
C40.80 - Malignant neoplasm of overlapping sites of bone and articular cartilage of unspecified limb——
C40.81 - Malignant neoplasm of overlapping sites of bone and articular cartilage of right limb——
C40.82 - Malignant neoplasm of overlapping sites of bone and articular cartilage of left limb——
C40.9 - Malignant neoplasm of unspecified bones and articular cartilage of limb——
C40.90 - Malignant neoplasm of unspecified bones and articular cartilage of unspecified limb——
C40.91 - Malignant neoplasm of unspecified bones and articular cartilage of right limb——
C40.92 - Malignant neoplasm of unspecified bones and articular cartilage of left limb——
C41 - Malignant neoplasm of bone and articular cartilage of other and unspecified sites——
C41.9 - Malignant neoplasm of bone and articular cartilage, unspecified——
C75 - Malignant neoplasm of other endocrine glands and related structures——
C75.0 - Malignant neoplasm of parathyroid gland——
C75.9 - Malignant neoplasm of endocrine gland, unspecified——
D35.1 - Benign neoplasm of parathyroid gland——
D44.2 - Neoplasm of uncertain behavior of parathyroid gland——
E05 - Thyrotoxicosis [hyperthyroidism]——
E05.0 - Thyrotoxicosis with diffuse goiter——
E05.1 - Thyrotoxicosis with toxic single thyroid nodule——
E05.9 - Thyrotoxicosis, unspecified——
E20 - Hypoparathyroidism——
E20.8 - Other hypoparathyroidism——
E20.9 - Hypoparathyroidism, unspecified——
E21 - Hyperparathyroidism and other disorders of parathyroid gland——
E21.0 - Primary hyperparathyroidism——
E21.1 - Secondary hyperparathyroidism, not elsewhere classified——
E21.2 - Other hyperparathyroidism——
E21.3 - Hyperparathyroidism, unspecified——
E23 - Hypofunction and other disorders of the pituitary gland——
E28 - Ovarian dysfunction——
E28.3 - Primary ovarian failure——
E28.31 - Premature menopause——
E28.310 - Symptomatic premature menopause——
E28.39 - Other primary ovarian failure——

Additional ICD10
ICD CODE AND DESCRIPTIONLCD CODENCD CODE
C40.0 - Malignant neoplasm of scapula and long bones of upper limb——
C40.00 - Malignant neoplasm of scapula and long bones of unspecified upper limb——
C40.01 - Malignant neoplasm of scapula and long bones of right upper limb——
C40.02 - Malignant neoplasm of scapula and long bones of left upper limb——
C40.1 - Malignant neoplasm of short bones of upper limb——
C40.10 - Malignant neoplasm of short bones of unspecified upper limb——
C40.11 - Malignant neoplasm of short bones of right upper limb——
C40.12 - Malignant neoplasm of short bones of left upper limb——
C40.2 - Malignant neoplasm of long bones of lower limb——
C40.20 - Malignant neoplasm of long bones of unspecified lower limb——
C40.21 - Malignant neoplasm of long bones of right lower limb——
C40.22 - Malignant neoplasm of long bones of left lower limb——
C40.3 - Malignant neoplasm of short bones of lower limb——
C40.30 - Malignant neoplasm of short bones of unspecified lower limb——
C40.31 - Malignant neoplasm of short bones of right lower limb——
C40.32 - Malignant neoplasm of short bones of left lower limb——
C40.8 - Malignant neoplasm of overlapping sites of bone and articular cartilage of limb——
C40.80 - Malignant neoplasm of overlapping sites of bone and articular cartilage of unspecified limb——
C40.81 - Malignant neoplasm of overlapping sites of bone and articular cartilage of right limb——
C40.82 - Malignant neoplasm of overlapping sites of bone and articular cartilage of left limb——
C40.9 - Malignant neoplasm of unspecified bones and articular cartilage of limb——
C40.90 - Malignant neoplasm of unspecified bones and articular cartilage of unspecified limb——
C40.91 - Malignant neoplasm of unspecified bones and articular cartilage of right limb——
C40.92 - Malignant neoplasm of unspecified bones and articular cartilage of left limb——
C41.0 - Malignant neoplasm of bones of skull and face——
C41.1 - Malignant neoplasm of mandible——
C41.2 - Malignant neoplasm of vertebral column——
C41.3 - Malignant neoplasm of ribs, sternum and clavicle——
C41.4 - Malignant neoplasm of pelvic bones, sacrum and coccyx——
C41.9 - Malignant neoplasm of bone and articular cartilage, unspecified——
C75.0 - Malignant neoplasm of parathyroid gland——
C75.1 - Malignant neoplasm of pituitary gland——
C75.2 - Malignant neoplasm of craniopharyngeal duct——
C75.3 - Malignant neoplasm of pineal gland——
C75.4 - Malignant neoplasm of carotid body——
C75.5 - Malignant neoplasm of aortic body and other paraganglia——
C75.8 - Malignant neoplasm with pluriglandular involvement, unspecified——
C75.9 - Malignant neoplasm of endocrine gland, unspecified——
D16.0 - Benign neoplasm of scapula and long bones of upper limb——
D16.00 - Benign neoplasm of scapula and long bones of unspecified upper limb——
D16.01 - Benign neoplasm of scapula and long bones of right upper limb——
D16.02 - Benign neoplasm of scapula and long bones of left upper limb——
D16.1 - Benign neoplasm of short bones of upper limb——
D16.10 - Benign neoplasm of short bones of unspecified upper limb——
D16.11 - Benign neoplasm of short bones of right upper limb——
D16.12 - Benign neoplasm of short bones of left upper limb——
D16.2 - Benign neoplasm of long bones of lower limb——
D16.20 - Benign neoplasm of long bones of unspecified lower limb——
D16.21 - Benign neoplasm of long bones of right lower limb——
D16.22 - Benign neoplasm of long bones of left lower limb——

References
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  • Clin Calcium. 2009 Dec;19(12):1815-21. [PMID:19949273]
  • J Cell Biochem. 1995 Mar;57(3):379-83. [PMID:7768973]
  • Clin Orthop Relat Res. 1988 Jan;(226):267-91. [PMID:3275514]
  • Alan Wu. Tietz Clinical Guide to Laboratory Tests, Fourth Edition. Saunders; 4 edition (June 13, 2006). ISBN-10: 0721679757