- Discussion:
- acute arthritis caused by CPPD crystal-induced inflammation;
- almost as common as gout & may perfectly mimic
gout during acute flare;
- pseudogout attacks occurring before age 50 are uncommon;
-
differential diagnosis:
- trauma:
- perhaps the majority of cases of chondrocalcinosis occur from trauma;
- ref: Localized chondrocalcinosis in traumatized joints. EE De Lange and TE Keats. Skeletal Radiology. Vol 14. 1985. p 249-256.
-
septic arthritis:
- pseudogout may be confused with septic arthritis;
- chondrocalcinosis of the meniscus occurs not only in otherwise healthy individuals in older age groups but also in definite association w/ several distinct metabolic disorders;
-
hemochromatosis;
-
hyperparathyroidism (most common);
- up to 30% of hyperparathyroid pts have chondrocalcinosis;
-
hypothyroidism;
-
gout:
-
hyperparathyroidism
- hypothyroidism
-
hemochromatosis
- ochronosis
- acromegaly
-
Paget's disease;
- Clinical Features:
- most often affects the knee and the wrists;
- CPPD Crystal Exam:
-
Crystal Examination of Synovial Fluid:
- Calcium pyrophosphate dihydrate crystals are visualized under compensated polarized light microscopy
- crystals may be more difficult to detect than MSU crystals because of their smaller size, more intraphagolysosomal location, & less brilliant colors;
- in contrast to MSU crystals, CPPD crystals show weak positive birefringency and have squared or rhomboidal shaped ends;
- aggregates do not show birefringence (or are weakly birefringent) under polarized light;
- alizarin red stain, can confirm that these clumps are masses of calcium crystals;
- Radiographic Analysis:
- punctate and linear densities in hyaline or
fibrocartilage, which are found in knee menisci, acetabular labrum, &
TFCC;
- Therapeutic Principles:
- aspiration of the involved joint and steroid injection, once diagnosis of infection has been excluded, will usually control symptoms;
-
indomethacin;
-
colchicine: not as useful for pseudogout;
A histological study of calcium pyrophosphate dihydrate crystal-deposition disease.
Clinical features of pseudogout attack. A survey of 50 cases.
Arthroscopy and chondrocalcinosis. A Fisseler-Eckhoff and KM Muller. Arthroscopy. Vol 8. 1992. p 98-104.
Pseudogout After Total Knee Arthroplasty.
Calcium Pyrophosphate Dihydrate Deposition Disease (Pseudogout) after Total Knee Arthroplasty.
Pseudogout after total knee arthroplasty.
