The HIV infection may be associated with myopathy. Polymyositis is the most common myopathy. The mitochondriopathies due to anti-retroviral drugs are also frequently observed. Therefore, all HIV-positive patient with a muscular symptoms should be offered a muscle biopsy.
A French study from muscle biopsies of patients with HIV infection
A morphological and immunohistochemical study were made from muscle biopsies of patients with HIV infection.
Forty-five patients infected with HIV, who had a muscle biopsy between 2005 and 2010, were selected from the computerized database of the Pitié Sapêtrière in Paris.
Polymyositis and mitochondriopathies, with the most common
Of the 50 biopsies, 86% were abnormal. In order of frequency, was found:
polymyositis in 53% of cases;
the mitochondriopathies in 32% of cases;
inclusion body myositis in 7% of cases.
A case of necrotizing myopathy, a case of fasciitis and one case of steroid myopathy were also observed. No infectious myositis was observed, and no case of immune restoration syndrome.
Polymyositis
Polymyositis associated with HIV is characterized by motor weakness usually proximal and symmetrical. The course is subacute over several weeks or months.
It is expressed clinically by the appearance of muscle weakness primarily affects shoulders, arms and thighs, and may be associated with muscle pain.
Muscle biopsy is essential for diagnosis.
In typical cases, it shows the association of a process of necrosis / regeneration myocyte with lesions of different ages, multifocal intrafascicular inflammatory infiltrates, and images of aggression focal necrotic myocytes not by inflammatory cells .
But in most cases, Burn The Fat Feed The Muscle the lesions are less well defined and limited to a few necrotic fibers and inflammatory infiltrates without evidence of focal myocyte aggression.
Mitochondrial myopathy
Zidovudine (AZT) is the main nuke can cause mitochondrial myopathy in HIV patients.
This toxic myopathy is reversible and occurs in patients receiving high cumulative doses.
Clinically, it presents itself as polymyositis.
But Histologically, there is the presence of ragged red fibers atrophy (“AZT fibers”) with marked myofibrillar alterations.
Mitochondrial DNA depletion is more marked that there is muscle weakness, myalgia, increased serum CPK [1] or “AZT fibers” on muscle biopsy.
The histo-enzymological abnormalities (partial deficiency of cytochrome C oxidase) are constant and represent a reliable marker.
The improvement of the clinical and decreased muscle enzymes after stopping zidovudine confirm the diagnosis.
The inclusion body myositis
Muscle biopsy shows when an inflammatory process associated with degenerative changes (atrophy myocyte, rimmed vacuoles, amyloid deposits, eosinophilic inclusions).
Achieve HIV status before any newly diagnosed polymyositis
Similarly, it will propose a muscle biopsy to patients with HIV infection presenting symptoms muscle.
Indeed, mitochondriopathies suites are frequently observed in anti-retroviral treatments.
Immunohistochemical analysis is essential for diagnosis.
The treatment is the same as for idiopathic polymyositis, including corticosteroids, azathioprine, methotrexate, cyclophosphamide, cyclosporine, and intravenous immunoglobulin.