[Diagnosis and treatment of calcium pyrophosphate crystal-induced arthropathy]

Chondrocalcinosis: Advances in Diagnostic Imaging

PURPOSE OF REVIEW

Calcium pyrophosphate deposition disease (CPPD) arises from calcium pyrophosphate deposition throughout the body, leading to different clinical syndromes that may be diagnosed using various imaging modalities. The purpose of this review is to highlight recent updates in the imaging of CPPD.

RECENT FINDINGS

Conventional radiography remains the initial test when imaging CPPD; but musculoskeletal ultrasound and conventional computed tomography (CT) may also assist in diagnosing and characterizing CPP deposits, with increased sensitivity. Dual-energy CT is also being used to differentiate CPP crystals from other crystal deposition diseases. CPP discitis has been diagnosed with MRI, but MRI has lower sensitivity and specificity than the aforementioned imaging studies in CPPD diagnosis. Assorted imaging modalities are increasingly used to diagnose CPPD involving atypical joints, avoiding invasive procedures. Each modality has its advantages and disadvantages. Future imaging may be able to provide more utility than what is currently available.

Bilateral Olecranon Bursitis - A Rare Clinical presentation of Calcium Pyrophosphate Crystal Deposition Disease

INTRODUCTION

Calcium pyrophosphate crystal deposition disease (CPPD) is the most common form of crystal arthropathy second only to gout. Common clinical presentation is an acute monoarticular arthritis commonly occurring in knee joints. We presented a case of bilateral olecranon bursitis in a calcium pyrophosphate crystal deposition disease.

CASE REPORT

A 42-year-old female patient is presented with golf ball sized painless swellings in the posterior aspect of her elbows. Elbow joints were clinically normal except for restriction of terminal flexion. X-ray showed mild erosion at the tip of olecranon. Excision biopsy of the swelling showed positive birefringent calcium pyrophosphate dehydrate crystals on the inner wall of the specimen on polarized light microscopy.

CONCLUSION

Bilateral olecranon bursitis may be part of the extraarticular manifestations of calcium pyrophosphate dihydrate crystal deposition disease with good prognosis following in toto bursa excision.

Unraveling the role of Mg(++) in osteoarthritis

Mg(++) is widely involved in human physiological processes that may play key roles in the generation and progression of diseases. Osteoarthritis (OA) is a complex joint disorder characterized by articular cartilage degradation, abnormal mineralization and inflammation. Magnesium deficiency is considered to be a major risk factor for OA development and progression. Magnesium deficiency is active in several pathways that have been implicated in OA, including increased inflammatory mediators, cartilage damage, defective chondrocyte biosynthesis, aberrant calcification and a weakened effect of analgesics. Abundant in vitro and in vivo evidence in animal models now suggests that the nutritional supplementation or local infiltration of Mg(++) represent effective therapies for OA. The goal of this review is to summarize the current understanding of the role of Mg(++) in OA with particular emphasis on the related molecular mechanisms involved in OA progression.

Chronic calcium pyrophosphate crystal inflammatory arthritis induced by extreme hypomagnesemia in short bowel syndrome

BACKGROUND

Short bowel syndrome (SBS) may induce a plethora of clinical symptoms ranging from underweight to nutrient-, vitamin- and electrolyte deficiencies. The objective of this case report is to illustrate how demanding the management of a 60 year old patient with SBS and recurrent joint attacks was for different medical disciplines.

CASE PRESENTATION

The patient with SBS presented with a body mass index of 16.5 kg/m2 after partial jejunoileal resection of the small intestine with a six year long history of recurrent pain attacks in multiple peripheral joints, chronic diarrhoea and food intolerances. Pain attacks occurred 4-5 times a week with a median consumption of 15 mg prednisone per day. The interdisciplinary workup after several gastroenterologic, rheumatologic, radiologic, psychiatric and orthopedic consultations is shown including successful treatment steps.Clinical diagnosis revealed no systemic inflammatory disease, but confirmed extreme hypomagnesemia (0.2 mmol/l) after reproducible pathological magnesium resorption tests as causative for chronic calcium pyrophosphate crystal inflammatory arthritis (pseudogout, chondrocalcinosis).Multidisciplinary treatment included application of colchicines, parenteral nutrition and magnesium substitution, antiperistaltic agents and avoidance of intolerant foods. Normalization of magnesium levels and a marked remission of joint attacks were achieved after six months with significant reduction of prednisone to 1.5 mg/day.

CONCLUSION

Despite the rarity of this condition, it is important to know that hypomagnesaemia may be associated with calcium pyrophosphate crystal inflammatory arthritis (chondrocalcinosis) and that SBS patients may be prone to develop extreme hypomagnesaemia causing recurrent joint attacks without systemic inflammation.

Ultrasonographic diagnosis of articular chondrocalcinosis

To investigate the role of high-frequency ultrasonography in the diagnosis of calcium pyrophosphate dihydrate (CPPD) calcifications, in the most commonly affected joints in CPPD disease. Sixty patients with knee effusion were included in the study. All patients underwent musculoskeletal ultrasonography (on the shoulder, elbow, wrist, and knee joints), radiological examination of the sites examined by US, and synovial fluid analysis (using polarized light microscopy). Out of 60 patients with knee effusion, ultrasonographic calcifications (knees, shoulders, and wrists) were present in 38 patients (63.3%) and out of those patients; 32 had calcification characteristic of CPPD crystals deposition (hyperechoic deposits) in the knee and wrist joints. Pattern II (punctate pattern) was the most common pattern of calcification. It was present in all patients who had wrist calcification (18 patients) and in the knee in either alone (21 patients) or in association with pattern I (hyperechoic band) and/or pattern III (hyperechoic nodular or oval deposits) (9 patients). The sensitivity of ultrasonography for the detection of calcification was 84.2% while that of plain radiography was 13.2%, the specificity of both ultrasonography and plain radiography for the detection of calcification was 100%, and ultrasonography is valuable for diagnosing articular chondrocalcinosis via the detection of calcifications within the joint cartilage and fibrocartilage. Both sensitivity and specificity are high for detecting CPPD deposits.

Validation of a radiographic scoring system for haemochromatosis arthropathy

BACKGROUND

Arthropathy is one of the earliest and most common manifestations of hereditary haemochromatosis with a significant impact on quality of life. Although its radiographic features are well known, there is no assessment tool for their evaluation.

OBJECTIVE

To develop and validate a novel scoring system for the evaluation of radiographic features of haemochromatosis arthropathy.

METHODS

A dichotomous scoring system assessing four radiographic features of haemochromatosis arthropathy and a 4-grade scale reflecting severity of radiographic change have been developed. Standard radiographs (hand, wrist, knee and ankle) of 170 subjects (116 male, 54 female) with genetically confirmed haemochromatosis and laboratory signs of iron overload were assessed by three readers and construct validity, feasibility and cross-sectional reliability (intrareader and inter-reader) were assessed.

RESULTS

Intrareader and inter-reader reliability as assessed by percentage pairwise agreement and Cohen's weighed κ were good to excellent for most features and locations evaluated. Radiographic scores correlated well with clinical parameters (bony swollen joint count, hand function and physician's global health assessment; Pearson's correlation, r²=0.18-0.62, p<0.0001). A complete set of radiographs took 3.4 ± 1.2 (mean ± SD) min to be assessed. An atlas of characteristic radiographic features was compiled.

CONCLUSION

A feasible and reliable radiological assessment tool for the evaluation of haemochromatosis arthropathy has been validated and an atlas of characteristic radiographic features provided.