CASE 11840 Published on 01.08.2014

Haemochromatosis - Signs in the hand

Section

Musculoskeletal system

Case Type

Clinical Cases

Authors

Maguire J

Glasgow Royal Infirmary,
NHS Greater Glasgow & Clyde,
Radiology; 84 Castle Street
G4 0SF Glasgow;
Email:jmag-ic-8@hotmail.co.uk
Patient

37 years, male

Categories
Area of Interest Musculoskeletal joint ; Imaging Technique Conventional radiography, MR
Clinical History
A right-handed gentleman with a known diagnosis of haemochromatosis was referred by his GP to the Rheumatology service due to pain and swelling of both hands. Routine radiographs were obtained as part of the initial work-up.
Imaging Findings
Most marked on the left, there is joint space loss at both the index and middle finger metacarpo-phalangeal joints (MCPJ). Classical 'hook-like' projections are demonstrated at the metacarpal heads of the index and middle fingers. A few flecks of soft tissue calcification are noted adjacent to the left index finger MCPJ and within the triangular fibrocartilage.

Coronal T1, T2 SPAIR and THRIVE imaging post gadolinium administration reveals extensive joint space loss with associated sub-articular cyst formation at the left index and middle finger MCPJ. There is evidence of post-contrast synovial enhancement around these joints.

Radiographs obtained two years later demonstrate progressive joint destruction.
Discussion
Primary haemochromatosis is a genetic disorder characterised by an autosomal recessive mutation in the HFE gene. This gene is responsible for controlling enteric iron absorption; hence in affected patients iron absorption is typically two to three times higher than in the general population [1]. Given the protective effect of iron loss during menstruation, haemochromatosis has a male predilection of 10-20:1 [2]. Excess iron overwhelms the storage capacity of the hepatic parenchyma and reticuloendothelial system, ultimately resulting in toxicity at various non-physiological deposition sites throughout the body.

Typical sites for the deposition of excess iron include the skin, liver, musculoskeletal system, pancreas and heart. Hence, patients often present with a combination of the following clinical features; bronzed-skin pigmentation, hepatomegaly, joint pain, diabetes, cardiomyopathy [3]. Pain and swelling of the hands is a common reason for referral to Rheumatology clinics, with plain radiographs forming an important part of a patient’s initial work up. In patients with haemochromatosis, the characteristic radiographic pattern of joint involvement suggests symptoms are related to the skeletal manifestations of the primary disease as opposed to a co-existing arthropathy.

First described by Schumacher in 1964, the radiographic findings of haemochromatosis are similar to those of osteoarthritis, with a reduction in joint space, subchondral sclerosis, cyst formation and osteophytosis all common findings [4]. Chondrocalcinosis often occurs, typically affecting the triangular fibrocartilage. Appearances may also resemble calcium pyrophosphate dihydrate deficiency disease (CPPD) although the pattern of joint involvement, with a predilection for the metacarpo-phalangeal joints, points towards the diagnosis of haemochromatosis. Indeed the classical description is of ‘hook-like’ osteophytes originating from the radial aspect of the heads of the 2nd and 3rd metacarpals [5]. By highlighting the inflammatory joint changes which may occur such as erosions, synovitis and bone marrow oedema [6], MRI is useful in patients with rapidly progressive disease. Whilst imaging findings are supportive, the overall diagnosis of haemochromatosis is usually made via liver biopsy or genetic testing.

Treatment involves regular venesection or iron chelation therapy to reduce circulating iron levels. Whilst these may improve symptoms and prolong survival, with therapy the 5-year survival rate increases from 33% to 89% [5], they have no effect on established skeletal disease. An awareness of the typical radiographic features and pattern of joint involvement is required for early diagnosis and treatment to prevent irreversible joint damage.

Haemochromatosis is a multi-system disorder with skeletal manifestations common to other rheumatological conditions but a classical distribution which often allows its diagnosis.
Differential Diagnosis List
Haemochromatosis arthropathy
Calcium pyrophosphate dihydrate deficiency disease
Osteoarthritis
Rheumatoid arthritis
Final Diagnosis
Haemochromatosis arthropathy
Case information
URL: https://www.eurorad.org/case/11840
DOI: 10.1594/EURORAD/CASE.11840
ISSN: 1563-4086