Crystal arthropathy is a class of joint disorders (called '' arthropathy'') that is characterized by the accumulation of tiny

crystal A crystal or crystalline solid is a solid material whose constituents (such as atoms, molecules, or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions. In addition, macros ...

s in one or more

joint A joint or articulation (or articular surface) is the connection made between bones, ossicles, or other hard structures in the body which link an animal's skeletal system into a functional whole.Saladin, Ken. Anatomy & Physiology. 7th ed. McGraw- ...

s. Polarizing microscopy and the application of other crystallographic techniques have improved the identification of different microcrystals including monosodium urate, calcium pyrophosphate dihydrate, calcium hydroxyapatite, and

calcium oxalate Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula or . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydr ...

Types

Causes

*Deposition of crystals in joints * Calcium pyrophosphate dihydrate crystal formation: **Increased production of inorganic pyrophosphate **Decreased levels of pyrophosphatase in

cartilage Cartilage is a resilient and smooth type of connective tissue. Semi-transparent and non-porous, it is usually covered by a tough and fibrous membrane called perichondrium. In tetrapods, it covers and protects the ends of long bones at the joints ...

**Decreased levels of

glycosaminoglycans Glycosaminoglycans (GAGs) or mucopolysaccharides are long, linear polysaccharides consisting of repeating disaccharide units (i.e. two-sugar units). The repeating two-sugar unit consists of a uronic acid, uronic sugar and an amino sugar, except i ...

Hyperparathyroidism Hyperparathyroidism is an increase in parathyroid hormone (PTH) levels in the blood. This occurs from a disorder either within the parathyroid glands ( primary hyperparathyroidism) or as response to external stimuli ( secondary hyperparathyroi ...

** Hemochromatosis ** Hypophosphatasia ** Hypomagnesemia *

Hydroxyapatite Hydroxyapatite (International Mineralogical Association, IMA name: hydroxylapatite) (Hap, HAp, or HA) is a naturally occurring mineral form of calcium apatite with the Chemical formula, formula , often written to denote that the Crystal struc ...

deposition: ** Tissue damage **

Hypercalcemia Hypercalcemia, also spelled hypercalcaemia, is a high calcium (Ca2+) level in the blood serum. The normal range for total calcium is 2.1–2.6 mmol/L (8.8–10.7 mg/dL, 4.3–5.2 mEq/L), with levels greater than 2.6 mmol/L def ...

** Hyperphosphatemia *

Calcium oxalate Calcium oxalate (in archaic terminology, oxalate of lime) is a calcium salt of oxalic acid with the chemical formula or . It forms hydrates , where ''n'' varies from 1 to 3. Anhydrous and all hydrated forms are colorless or white. The monohydr ...

deposition: **Enhanced production of

oxalic acid Oxalic acid is an organic acid with the systematic name ethanedioic acid and chemical formula , also written as or or . It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name i ...

due to

enzyme An enzyme () is a protein that acts as a biological catalyst by accelerating chemical reactions. The molecules upon which enzymes may act are called substrate (chemistry), substrates, and the enzyme converts the substrates into different mol ...

defect **Poor excretion of

kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

**Excessive

ascorbic acid Ascorbic acid is an organic compound with formula , originally called hexuronic acid. It is a white solid, but impure samples can appear yellowish. It dissolves freely in water to give mildly acidic solutions. It is a mild reducing agent. Asco ...

intake in

Risk factors

Obesity Obesity is a medical condition, considered by multiple organizations to be a disease, in which excess Adipose tissue, body fat has accumulated to such an extent that it can potentially have negative effects on health. People are classifi ...

Kidney failure Kidney failure, also known as renal failure or end-stage renal disease (ESRD), is a medical condition in which the kidneys can no longer adequately filter waste products from the blood, functioning at less than 15% of normal levels. Kidney fa ...

* Hyperphosphatemia *

* Tissue damage ( dystrophic calcification)

Diagnosis

Differential diagnosis

Septic arthritis Acute septic arthritis, infectious arthritis, suppurative arthritis, pyogenic arthritis, osteomyelitis, or joint infection is the invasion of a joint by an infectious agent resulting in joint inflammation. Generally speaking, symptoms typica ...

* Type IIa hyperlipoproteinemia *

Amyloidosis Amyloidosis is a group of diseases in which abnormal proteins, known as amyloid fibrils, build up in tissue. There are several non-specific and vague signs and symptoms associated with amyloidosis. These include fatigue, peripheral edema, weigh ...

* Multicentric reticulohistiocytosis *

* Spondyloarthropathy *

Rheumatoid arthritis Rheumatoid arthritis (RA) is a long-term autoimmune disorder that primarily affects synovial joint, joints. It typically results in warm, swollen, and painful joints. Pain and stiffness often worsen following rest. Most commonly, the wrist and h ...

Treatment

1. Steroid - options are intra-articular injection, oral steroid, or intramuscular injection of steroid. Intra-articular steroid + lido w/o (I like triamcinolone the best) 20 mg for small joints is perfect. For the intramuscular injection, I like 40 mg triamcinolone and 20 mg dexamethasone in the same syringe injected into the gluteus. For the oral steroid, I like Prednisone 40 mg every morning for seven days. The prescription will read prednisone 20 mg, two tabs PO Qa.m. x 7d, #14 0RF. 2. Colchicine 0.6 mg tabs - two tabs by mouth once and then one tab by mouth an hour later. 3. NSAID - I prefer 500 mg of naproxen twice a day for seven days. Just be careful with the NSAID and steroid combination. If prescribing oral steroids, I put patients on famotidine 40 mg one tablet by mouth twice a day for 14 days Do not prescribe allopurinol for acute gout flair. Wait until they are six weeks resolved to initiate that, otherwise you can cause an acute flare/worsening of the gout. However, they are already on allopurinol, continue it.

References

External links

{{Diseases of the musculoskeletal system and connective tissue Inflammatory polyarthropathies