pyrophosphate and Hemochromatosis

Topics: Animals; Arthropathy, Neurogenic; Calcium Pyrophosphate; Cartilage, Articular; Cholesterol; Chondrocalcinosis; Crystallization; Diphosphates; Disease Models, Animal; Durapatite; Hand; Hemochromatosis; Humans; Hydroxyapatites; Knee Joint; Menisci, Tibial; Ochronosis; Osteoarthritis; Postoperative Complications; Radiography; Shoulder Joint; Uric Acid

Inorganic pyrophosphate (PPi) levels were estimated by radiometric assay in urine and in synovial fluid (SF) from asymptomatic, nonarthritic knees of patients with untreated metabolic disease and normal controls. SF PPi was significantly elevated in patients with hyperparathyroidism (mean +/- SEM 19 +/- 3 microM; n = 9), hemochromatosis (23 +/- 5 microM; n = 6), and hypomagnesemia (27 +/- 0.1 microM; n = 2) compared with normal subjects (10 +/- 0.5 microM, n = 50), and was low in patients with hypothyroidism (4.2 +/- 2.3 microM; n = 11) (P less than 0.05 all comparisons). Urinary PPi was elevated only in those with hypophosphatasia. Local elevation of ionic PPi may be relevant to the mechanism of crystal formation in metabolic diseases predisposing to calcium pyrophosphate dihydrate (CPPD) crystal deposition. The finding of low SF PPi levels in patients with hypothyroidism further questions the association between this condition and CPPD.

Topics: Adult; Aged; Aged, 80 and over; Calcium Pyrophosphate; Creatinine; Crystallization; Diphosphates; Endocrine System Diseases; Female; Hemochromatosis; Humans; Hyperparathyroidism; Hypophosphatasia; Hypothyroidism; Magnesium Deficiency; Male; Metabolic Diseases; Middle Aged; Synovial Fluid

To determine the physical-chemical effects of [Fe++] and [Fe ] on calcium pyrophosphate dihydrate (CPPD) crystal formation de novo, we studied CPPD crystal formation in an established model aqueous solution mixture system using physiological concentrations of Na+, Mg++, Ca++, C1-. We found that [Fe++] greater than 1 microM or [Fe ] greater than or equal to 100 microM inhibits CPPD crystal formation under conditions of [Ca++] = 1.5 mM, [Pi] = 0.1 mM, and [PPi] = 0.1 mM that simulate CPPD formation in vivo. These experiments suggest that at biological concentrations, Fe++ acts to inhibit CPPD formation but that [Fe++] depletion therapy by removal of inhibition effects may facilitate CPPD crystal formation in articular tissues.

Topics: Calcium Pyrophosphate; Chondrocalcinosis; Crystallization; Diphosphates; Ferric Compounds; Ferrous Compounds; Hemochromatosis; Humans

In a series of 28 long-term dialysis patients with musculoskeletal complaints, the radiologic findings in six cases resembled those occurring in the arthropathy of idiopathic calcium pyrophosphate dihydrate deposition (CPPD) disease. These findings included osteophytes, subchondral cysts, and cartilage loss in the metacarpophalangeal joints, patellofemoral joints, wrists, and shoulders. Chondrocalcinosis was present in three of the six cases. There were no significant differences in renal function or levels of serum calcium, phosphorus, iron, ferritin, aluminum, or parathormone between these patients and a control group matched for sex and age. Long-term dialysis may be associated with a metabolic arthritis similar to the arthritis which occurs in CPPD deposition disease. The etiology may include deposition of CPPD crystals, hydroxyapatite, or other calcium-containing substances in joints, or it may be related to a number of dialysis-induced metabolic abnormalities.

Topics: Arthritis; Arthrography; Calcinosis; Calcium Pyrophosphate; Cartilage, Articular; Cysts; Diphosphates; Hemochromatosis; Humans; Hyperparathyroidism, Secondary; Iron; Kidney Failure, Chronic; Renal Dialysis

Radiographic features of hand and wrist involvement in 26 patients with hemochromatosis and in 26 patients with idiopathic calcium pyrophosphate dihydrate (CPPD) crystal deposition disease were compared. Two radiologists independently examined the radiographs without knowledge of the specific group to which the patient belonged. The results of this study clearly establish that structural joint diseases in the two disorders are not identical. Characteristic findings allow the radiologist to favor one diagnosis over the other. These radiographic differences indicate that the arthropathy of hemochromatosis is related to factors additional to the presence of CPPD crystals, specifically, the more prevalent narrowing of the metacarpophalangeal joint spaces, including those in the fourth and fifth digits, peculiar hook-like osteophytes on the radial aspect of the metacarpal heads, and less prevalent separation of the scaphoid and the lunate.

Topics: Adult; Aged; Calcium Metabolism Disorders; Calcium Pyrophosphate; Diagnosis, Differential; Diphosphates; Female; Hand; Hemochromatosis; Humans; Joint Diseases; Male; Metacarpophalangeal Joint; Middle Aged; Radiography; Wrist Joint

Nine patients with chronic iron overload, resulting from either repeated transfusions or hemochromatosis, had bone scans that were characterized by a reduction of bony uptake, marked increase in renal activity, and a significant increase in soft-tissue accumulation of 99mTc-labeled bone-seeking agents. These findings were supported by semiquantitative computer analysis. The probable mechanisms of altered biodistribution and the possible role of serum ferritin are discussed. The importance of realizing the effect of excess iron on skeletal scintigraphy is further emphasized by the results of bone scanning in another patient in whom acute iron overload following infusion of iron-dextran resulted in excessive blood pool labeling.

Topics: Adolescent; Adult; Aged; Bone and Bones; Child, Preschool; Diphosphates; Female; Hemochromatosis; Humans; Iron; Kidney; Male; Middle Aged; Radionuclide Imaging; Spine; Technetium; Technetium Tc 99m Pyrophosphate

Five cases of hemochromatosis arthropathy are presented and the distinctive radiological features of the disease are described. Although the condition is typically degenerative, showing subchondral cyst formation, sclerosis, and thinning of cartilage, its distribution is characteristic. Selective degenerative changes of the second and third metacarpophalangeal joints are striking, particularly in the hands, while abnormalities in the intercarpal joints are variable and the interphalangeal joints are spared. Chondrocalcinosis involving both fibrous and hyaline cartilage is frequently seen as well, particularly in the large joints. The calcification is due to deposition of calcium pyrophosphate crystals, perhaps resulting from iron inhibition of pyrophosphatase.

Topics: Adult; Aged; Arthritis; Arthritis, Rheumatoid; Calcium Phosphates; Chondrocalcinosis; Diagnosis, Differential; Diphosphates; Elbow Joint; Finger Joint; Hemochromatosis; Hip Joint; Humans; Joint Diseases; Knee Joint; Male; Middle Aged; Osteoarthritis; Radiography; Shoulder Joint; Spine; Synovial Membrane; Wrist Joint

Topics: Age Factors; Alkaline Phosphatase; Calcification, Physiologic; Calcinosis; Diphosphates; Hemochromatosis; Humans; Iron; Joint Diseases

Topics: Acromegaly; Adult; Calcinosis; Calcium Phosphates; Cartilage Diseases; Diagnosis, Differential; Diphosphates; Gout; Hemochromatosis; Humans; Hyperparathyroidism; Joints; Male; Microscopy, Polarization; Middle Aged; Radiography; Terminology as Topic