Dysferlinopathy in Tunisia: clinical spectrum, genetic background and prognostic profile

Dysferlinopathy is a rare group of hereditary muscular dystrophy with an autosomal recessive mode of inheritance caused by a mutation in the DYSF gene. It encodes for the dysferlin protein, which has a crucial role in multiple cellular processes, including muscle fiber membrane repair. This deficit has heterogeneous clinical presentations. In this study, we collected 20 Tunisian patients with a sex ratio of 1 and a median age of 50.5 years old (Interquartile range (IQR) = [36,5-54,75]). They were followed for periods ranging from 5 to 48 years. The median age at onset was 17 years old (IQR = [16,8-28,4]). Five major phenotypes were identified: Limb-girdle muscular dystrophy (LGMDR2) (35%), a proximodistal phenotype (35%), Miyoshi myopathy (10%),  Distal myopathy with anterior tibial onset (DMAT) (10%), and asymptomatic HyperCKemia (10%). At the last evaluation, more than half of patients (55%) were on wheelchair. Loss of ambulation occurred generally during the fourth decade. After 20 years of disease progression, two patients with a proximodistal phenotype (10%) developed dilated cardiomyopathy and mitral valve regurgitation. Restrictive respiratory syndrome was observed in three patients (DMAT: 1 patient, proximodistal phenotype: 1 patient, LGMDR2: 1 patient). Genetic study disclosed five mutations. We observed clinical heterogeneity between families and even within the same family. Disease progression was mainly slow to intermediate regardless of the phenotype.

Aluminum adjuvants of vaccines injected into the muscle: Normal fate, pathology and associated disease

Aluminum oxyhydroxide (Alhydrogel(®)) is a nano-crystalline compound forming aggregates that has been introduced in vaccine for its immunologic adjuvant effect in 1926. It is the most commonly used adjuvant in human and veterinary vaccines but mechanisms by which it stimulates immune responses remain ill-defined. Although generally well tolerated on the short term, it has been suspected to occasionally cause delayed neurologic problems in susceptible individuals. In particular, the long-term persistence of aluminic granuloma also termed macrophagic myofasciitis is associated with chronic arthromyalgias and fatigue and cognitive dysfunction. Safety concerns largely depend on the long biopersistence time inherent to this adjuvant, which may be related to its quick withdrawal from the interstitial fluid by avid cellular uptake; and the capacity of adjuvant particles to migrate and slowly accumulate in lymphoid organs and the brain, a phenomenon documented in animal models and resulting from MCP1/CCL2-dependant translocation of adjuvant-loaded monocyte-lineage cells (Trojan horse phenomenon). These novel insights strongly suggest that serious re-evaluation of long-term aluminum adjuvant phamacokinetics and safety should be carried out.

Dermatomyositis: factors predicting relapse

BACKGROUND

The course of dermatomyositis (DM) can be chronic with relapses, which are associated with major morbidity.

OBJECTIVE

The aim of this study was to identify presentation features that predict DM relapses.

METHODS

We retrospectively reviewed data of patients with DM recorded from 1990 to 2011, including muscle biopsy results. Characteristics of patients with and without relapses were compared. Hazard ratios (HRs) were estimated using a Cox model.

RESULTS

We identified 34 patients, with a mean age of 46 ± 17 years (range, 18-77) and 24 (71%) women. The muscle and skin abnormalities relapsed in 21 (61%) patients. By univariate analysis, two presentation features were significantly associated with a subsequently relapsing course, namely, dysphonia [HR = 3.2 (1.2-8.5)] and greater skin lesion severity defined as a Cutaneous Disease Area Severity Index [CDASI] > 20 [HR = 3.5 (1.2-7.9)].

CONCLUSION

Dysphonia and skin lesion severity at disease onset must be recorded, as they significantly predict a relapsing disease course.

Biopersistence and brain translocation of aluminum adjuvants of vaccines

Aluminum oxyhydroxide (alum) is a crystalline compound widely used as an immunological adjuvant of vaccines. Concerns linked to the use of alum particles emerged following recognition of their causative role in the so-called macrophagic myofasciitis (MMF) lesion detected in patients with myalgic encephalomyelitis/chronic fatigue/syndrome. MMF revealed an unexpectedly long-lasting biopersistence of alum within immune cells in presumably susceptible individuals, stressing the previous fundamental misconception of its biodisposition. We previously showed that poorly biodegradable aluminum-coated particles injected into muscle are promptly phagocytosed in muscle and the draining lymph nodes, and can disseminate within phagocytic cells throughout the body and slowly accumulate in brain. This strongly suggests that long-term adjuvant biopersistence within phagocytic cells is a prerequisite for slow brain translocation and delayed neurotoxicity. The understanding of basic mechanisms of particle biopersistence and brain translocation represents a major health challenge, since it could help to define susceptibility factors to develop chronic neurotoxic damage. Biopersistence of alum may be linked to its lysosome-destabilizing effect, which is likely due to direct crystal-induced rupture of phagolysosomal membranes. Macrophages that continuously perceive foreign particles in their cytosol will likely reiterate, with variable interindividual efficiency, a dedicated form of autophagy (xenophagy) until they dispose of alien materials. Successful compartmentalization of particles within double membrane autophagosomes and subsequent fusion with repaired and re-acidified lysosomes will expose alum to lysosomal acidic pH, the sole factor that can solubilize alum particles. Brain translocation of alum particles is linked to a Trojan horse mechanism previously described for infectious particles (HIV, HCV), that obeys to CCL2, signaling the major inflammatory monocyte chemoattractant.

Macrophagic myofasciitis: characterization and pathophysiology

Aluminium oxyhydroxide (alum), a nanocrystalline compound forming agglomerates, has been used in vaccines for its immunological adjuvant effect since 1927. Alum is the most commonly used adjuvant in human and veterinary vaccines, but the mechanisms by which it stimulates immune responses remain incompletely understood. Although generally well tolerated, alum may occasionally cause disabling health problems in presumably susceptible individuals. A small proportion of vaccinated people present with delayed onset of diffuse myalgia, chronic fatigue and cognitive dysfunction, and exhibit very long-term persistence of alum-loaded macrophages at the site of previous intramuscular (i.m.) immunization, forming a granulomatous lesion called macrophagic myofasciitis (MMF). Clinical symptoms associated with MMF are paradigmatic of the recently delineated 'autoimmune/inflammatory syndrome induced by adjuvants' (ASIA). The stereotyped cognitive dysfunction is reminiscent of cognitive deficits described in foundry workers exposed to inhaled Al particles. Alum safety concerns will largely depend on whether the compound remains localized at the site of injection or diffuses and accumulates in distant organs. Animal experiments indicate that biopersistent nanomaterials taken up by monocyte-lineage cells in tissues, such as fluorescent alum surrogates, can first translocate to draining lymph nodes, and thereafter circulate in blood within phagocytes and reach the spleen, and, eventually, slowly accumulate in the brain.

Complications musculaires de l’infection par le virus de l’immunodéficience humaine (VIH) à l’ère des trithérapies

Introduction of highly active antiretroviral therapy (HAART) has dramatically modified the natural history of HIV disease, but lengthening the survival of HIV-infected individuals has been associated with an increasing prevalence of iatrogenic conditions. Muscular complications of HIV infection are classified as follows: (1) HIV-associated myopathies and related conditions including polymyositis, inclusion-body myositis, nemaline myopathy, diffuse infiltrative lymphocytosis syndrome (DILS), HIV-wasting syndrome, vasculitis, myasthenic syndromes, and chronic fatigue; (2) iatrogenic conditions including mitochondrial myopathies, HIV-associated lipodystrophy syndrome, and immune restoration syndrome; (3) opportunistic infections and tumor infiltrations of skeletal muscle; and (4) rhabdomyolysis. These features are described in the present review.

[Intravascular large cell lymphoma revealed by diffuse telangiectasia and cauda equina syndrome]

BACKGROUND

Intravascular lymphoma is a rare disease with usually fatal outcome, characterized by the proliferation within the lumen of small blood vessels of neoplastic large lymphoid cells of B-cell origin. We report a case of intravascular lymphoma revealed by diffuse telangiectasia and cauda equina syndrome.

CASE REPORT

A 64-year-old Vietnamese woman presented with unexpected fever and weight loss. Three months after the onset of the first symptoms, an oedema appeared on the lower limbs and the trunk, followed by the eruption of diffuse superficial telangiectasia. Neurologic examination revealed a cauda equina syndrome. The diagnosis of intravascular B cell lymphoma was established on cutaneous and muscular biopsy specimen. A moderate hemophagocytic syndrome was observed, confirmed by bone marrow biopsy. Corticosteroid therapy was started, followed by combination chemotherapy yielding complete response. Six months later death occurred, without evidence of relapse of intravascular lymphoma.

DISCUSSION

Clinical presentation of intravascular lymphoma is often confusing, mimicking systemic disease, with a predilection for skin and nervous system involvement. Diagnosis is difficult and often an autopsy finding. Prognosis is generally poor, but favourable responses to chemotherapy have been observed after early diagnosis and treatment. The pathogenesis of intravascular lymphoma remains unknown. Dysfunction of cell-endothelial interaction affecting adhesion molecules has been suspected. The implication of Epstein-Barr virus in intravascular lymphoma remains controversial.

Oligoclonal T-cells in blood and target tissues of patients with anti-Hu syndrome

T-cell clones of unknown significance (TCUS), assessed by monoclonal or oligoclonal T-cell patterns in PCR-DGGE, were detected in blood of 7/9 patients with anti-Hu syndrome. Clonal patterns were also detected in 2/2 neoplastic lymph nodes, and in 2/2 inflamed dorsal root ganglia from three patients. Only some T-cell clones found in target tissues were also detected in blood or non-target tissues, and likely corresponded to TCUS. In one patient, an identical T-cell clone was found in both neoplastic lymph node tissue and dorsal root ganglia, but not in blood. Dorsal root-infiltrating lymphocytes were cytotoxic CD8(+) TIA-1(+) T-cells. They were often found in close contact to sensory neurons, most of which expressed MHC-1. Taken together, these data support a direct effector role of cytotoxic CD8(+) T-cells, the same clones being likely operative in sensory neuron damage and immune-mediated tumor growth control.

Impaired redox status and cytochrome c oxidase deficiency in patients with polymyalgia rheumatica

OBJECTIVE

To evaluate redox status and muscular mitochondrial abnormalities in patients with polymyalgia rheumatica (PMR).

METHODS

Prospective evaluation of deltoid muscle biopsy in 15 patients with PMR. Fifteen subjects matched for age and sex, with histologically normal muscle and without clinical evidence of myopathy, were used as controls. Cryostat sections of muscle were processed for conventional dyes, cytochrome c oxidase (COX), usual histochemical reactions, and Sudan black. A total of 300-800 fibres was examined in each case. Blood lactate, pyruvate, and lactate/pyruvate ratio were determined in all patients.

RESULTS

Ragged red fibres were found in eight patients with PMR and accounted for 0-0.5% of fibres. Focal COX deficiency was found in 14 (93%) of 15 patients and in nine (60%) of 15 controls. COX deficient fibres were more common in patients with PMR (range 0-2.5%; mean 0.9%) than in controls (range 0-1.2%; mean 0.3%) (paired t test, p=0.001). Seven (47%) of 15 patients had high blood lactate levels (1.50-2.60 mmol/l) or high blood lactate/pyruvate ratios (22-25).

CONCLUSIONS

PMR is associated with mitochondrial abnormalities not solely related to the aging process.

Macrophagic myofasciitis lesions assess long-term persistence of vaccine-derived aluminium hydroxide in muscle

Macrophagic myofasciitis (MMF) is an emerging condition of unknown cause, detected in patients with diffuse arthromyalgias and fatigue, and characterized by muscle infiltration by granular periodic acid-Schiff's reagent-positive macrophages and lymphocytes. Intracytoplasmic inclusions have been observed in macrophages of some patients. To assess their significance, electron microscopy was performed in 40 consecutive cases and chemical analysis was done by microanalysis and atomic absorption spectrometry. Inclusions were constantly detected and corresponded to aluminium hydroxide, an immunostimulatory compound frequently used as a vaccine adjuvant. A lymphocytic component was constantly observed in MMF lesions. Serological tests were compatible with exposure to aluminium hydroxide-containing vaccines. History analysis revealed that 50 out of 50 patients had received vaccines against hepatitis B virus (86%), hepatitis A virus (19%) or tetanus toxoid (58%), 3-96 months (median 36 months) before biopsy. Diffuse myalgias were more frequent in patients with than without an MMF lesion at deltoid muscle biopsy (P < 0.0001). Myalgia onset was subsequent to the vaccination (median 11 months) in 94% of patients. MMF lesion was experimentally reproduced in rats. We conclude that the MMF lesion is secondary to intramuscular injection of aluminium hydroxide-containing vaccines, shows both long-term persistence of aluminium hydroxide and an ongoing local immune reaction, and is detected in patients with systemic symptoms which appeared subsequently to vaccination.

Focal neurological complications of handcuff application

The application of handcuffs may result in compression neuropathies at the wrist. The frequency of these complications is unknown. Twelve of 190 (6.3%) consecutive subjects kept in police custody presented distal neurological symptoms possibly related to handcuff application. The duration of handcuffing was significantly longer in patients with neurological symptoms than in patients without neurological symptoms (mean +/- SD: 3.7+/-5.2 h vs. 1.8+/-2.6 h, P = 0.02). A long duration of handcuff application and, possibly, the existence of somnolence or acute alcohol intoxication could be predisposing factors to handcuff neuropathy. A prospective study of clinical and electrophysiological detection and follow up is needed.

Macrophagic myofasciitis associated with inclusion body myositis: a report of three cases

We describe three patients with macrophagic myofasciitis and inclusion body myositis. All patients fulfilled diagnostic criteria for inclusion body myositis and myopathologic criteria for macrophagic myofasciitis. In the three cases macrophagic myofasciitis complicated the evolution of a known and painless inclusion body myositis and was diagnosed in a repeated deltoid biopsy because of the appearance of myalgia during the course of inclusion body myositis in all cases. The unexpected appearance of myalgia during the course of painless inclusion body myositis must arouse the suspicion of an association of another inflammatory muscle disease, macrophagic myofasciitis.

Central nervous system disease in patients with macrophagic myofasciitis

Macrophagic myofasciitis (MMF), a condition newly recognized in France, is manifested by diffuse myalgias and characterized by highly specific myopathological alterations which have recently been shown to represent an unusually persistent local reaction to intramuscular injections of aluminium-containing vaccines. Among 92 MMF patients recognized so far, eight of them, which included the seven patients reported here, had a symptomatic demyelinating CNS disorder. CNS manifestations included hemisensory or sensorimotor symptoms (four out of seven), bilateral pyramidal signs (six out of seven), cerebellar signs (four out of seven), visual loss (two out of seven), cognitive and behavioural disorders (one out of seven) and bladder dysfunction (one out of seven). Brain T(2)-weighted MRI showed single (two out of seven) or multiple (four out of seven) supratentorial white matter hyperintense signals and corpus callosum atrophy (one out of seven). Evoked potentials were abnormal in four out of six patients and CSF in four out of seven. According to Poser's criteria for multiple sclerosis, the diagnosis was clinically definite (five out of seven) or clinically probable multiple sclerosis (two out of seven). Six out of seven patients had diffuse myalgias. Deltoid muscle biopsy showed stereotypical accumulations of PAS (periodic acid-Schiff)-positive macrophages, sparse CD8+ T cells and minimal myofibre damage. Aluminium-containing vaccines had been administered 3-78 months (median = 33 months) before muscle biopsy (hepatitis B virus: four out of seven, tetanus toxoid: one out of seven, both hepatitis B virus and tetanus toxoid: two out of seven). The association between MMF and multiple sclerosis-like disorders may give new insights into the controversial issues surrounding vaccinations and demyelinating CNS disorders. Deltoid muscle biopsy searching for myopathological alterations of MMF should be performed in multiple sclerosis patients with diffuse myalgias.

Localized neurological necrotizing vasculitides. Three cases with isolated mononeuritis multiplex

Localized vasculitic neuropathies are increasingly reported. We describe 3 cases of peripheral neuropathy with necrotizing vasculitis confined to nerves and muscles without systemic involvement. These neuropathies were severe and relapsing, in contrast to a usually benign prognosis. Our cases appear to be isolated vasculitic neuropathies, with vasculitis strictly limited to the peripheral neuromuscular system without nonspecific clinical and/or biological systemic involvement.

Cytochrome c oxidase deficiency in the muscle of patients with zidovudine myopathy is segmental and affects both mitochondrial DNA- and nuclear DNA-encoded subunits

Zidovudine (AZT) can induce a mitochondrial disorder associated with mitochondrial (mt) DNA depletion affecting skeletal muscle, heart, and liver. Zidovudine myopathy is characterized by ragged-red fibers and partial cytochrome c oxidase (COX) deficiency. We evaluated at a single fiber level the expression of COX II (mtDNA-encoded) and COX IV (nuclear DNA-encoded) subunits in 12 HIV-infected patients with zidovudine myopathy. We also evaluated COX activity on longitudinal muscle sections in one patient. In all patients, evaluation of the expression of COX II and COX IV subunits showed focal deficiency. All fibers negative for COX II or COX IV were negative by COX histochemistry; 32-92% (median 61%) of COX-negative fibers were negative for COX II antigens, and 7-58% (median 28%) were negative for COX IV antigens. One hundred and thirty-nine of 317 COX-negative fibers 139 (43.8%) were selectively negative for COX II; 28 of 317 (8.8%) COX-negative fibers were selectively negative for COX IV. A study of longitudinal distribution of COX activity demonstrated that COX deficiency was segmental with blurred borders, as previously observed in patients with myoclonus epilepsy with ragged-red fibers. We conclude that proteins encoded by mtDNA are predominantly, but not exclusively, involved in zidovudine myopathy. Our results confirm the value of single muscle fiber evaluation in the assessment of mitochondrial abnormalities related to zidovudine.

Gallium-67 scintigraphy in macrophagic myofasciitis

OBJECTIVE

To evaluate gallium-67 (67Ga) uptake and the value of 67Ga scintigraphy for diagnosis of macrophagic myofasciitis (MMF), a recently identified inflammatory myopathy.

METHODS

Twelve consecutive patients with MMF confirmed by muscle biopsy, 10 with polymyositis, 10 with sarcoidosis, 8 with fibromyalgia, and 10 with lymphoma without muscle symptoms (serving as normal controls for muscle) were included. Patients received 1.8 MBq 67Ga per kg body weight by intravenous injection, and scintigraphy was performed with a 2-head gamma camera. The various views were acquired for the 3 main photopeaks of 67Ga 48 hours after infusion, and were analyzed in 2 blinded experiments by nuclear physicians. A semiquantitative scale was used to compare the uptake of 67Ga in the vascular soft tissue background with that in the muscles or joints of MMF patients, and with that in the normal controls.

RESULTS

The MMF patients (4 men and 8 women, mean +/- SD age 47.8 +/- 8.7 years) had chronic myalgia (n = 11; predominantly in the lower limbs), asthenia (n = 10), arthralgia (n = 7), mild muscle weakness (n = 5), and high serum creatine kinase levels (n = 6). All MMF patients had significantly higher levels of 67Ga uptake in the muscle and para-articular areas than that recorded for the soft tissue background and for the controls. Muscle uptake was bilateral, symmetric, and homogeneous, and predominantly localized in the legs. No linear enhancement corresponding to fascias or synovial involvement was observed. In patients with polymyositis, symmetric, but heterogeneous, 67Ga uptake was observed in muscle, but not in the fascia. In patients with sarcoidosis, 67Ga uptake was nodular and heterogeneous in muscle, was not detected in the fascia, and was suggestive of synovial involvement in the joints. The uptake of 67Ga in fibromyalgic patients was similar to that in normal controls and to that in the soft tissue background.

CONCLUSION

MMF is a new condition involving characteristic changes that can be detected by deltoid muscle biopsy. It usually manifests as a weakly specific, chronic arthromyalgic syndrome that predominates in the lower limbs. 67Ga scintigraphy is a noninvasive method that may make it easier to differentiate MMF from fibromyalgia and sarcoidosis.

[Classification of muscle cells]

Muscle cells, including smooth muscle cells, cardiac muscle fibers and skeletal muscle fibers, are specialized for generation of movement and force in a specific direction. Smooth muscle cells are mononucleate cells, isolated or grouped in layers in various tissues, or rarely forming individualized muscles. Smooth muscle cell contraction is slow and depends on the autonomic nervous system. Cardiac muscle cells are mononucleate striated cells, with fast, rhythmic, spontaneous contractions. Skeletal muscle fibers are multinucleate cells at the origin of voluntary movements. According to morphological and functional criteria, skeletal muscle fibers are classified as type I fibers (slow-twitch oxidative), type IIA fibers (fast-twitch oxidative glycolytic) or type IIB fibers (fast-twitch glycolytic).

[Macrophagic myofasciitis. Study and Research Group on Acquired and Dysimmunity-related muscular diseases (GERMMAD)]

MACROPHAGIC MYOFASCIITIS: A most unusual inflammatory myopathy, first described by Germmad had been reported with increasing frequency since 1993 in the leading French myopathology centers. We present our experience with this new disease: macrophagic myofasciitis.

CLINICAL FEATURES

By November 1999, 70 cases of macrophagic myofasciitis had been recorded since our first description. The first 22 patients (sex ratio M/F = 1:3) referred with the presumptive diagnosis of polymyositis (n = 11), polymyalgia rheumatica (n = 5), mitochondrial cytopathy (n = 4), and congenital myopathy or muscle dystrophy (n = 1 each). Symptoms included myalgia (91%), anthralgia (68%), marked asthenia (55%), muscle weakness (45%), and fever (32%).

LABORATORY FINDINGS

Abnormal laboratory findings included elevated CK levels (50%), markedly increased erythrocyte sedimentation rate (37%), and myopathic EMG (35%). Muscle biopsy showed a unique myopathological pattern characterized by: i) centripetal infiltration of epimysium, perimysium and perifascicular endomysium by sheets of large cells of the monocyte/macrophage lineage (CD68+, CD1a-, S100-, with a PAS-positive content; ii) absence of necrosis, of both epithelioid and giant cells, and of mitotic figures; iii) presence of occasional CD8+ T-cells; iv) inconspicuous muscle fiber damage. The picture was easily distinguishable from sarcoid myopathy and fasciitis-panniculitis syndromes. The infectious diseases know to be associated with reactive histiocytes, including Whippleís disease, Mycobacterium avium intracellulare infection and malakoplakia, could not be documented. Patients improved under corticosteroid therapy and/or immunomodulatory therapeutic

CONCLUSION

A new inflammatory muscle disorder, characterized by a distinctive pathological pattern of macrophagic myofasciitis is emerging in France.

Differential expression of the IL-1 system components during in vitro myogenesis: implication of IL-1beta in induction of myogenic cell apoptosis

We evaluated the expression of IL-1 system by normal human myogenic cells during in vitro myogenesis and the effect of exogenous IL-1beta. Expression of IL-1alpha and beta, IL-1 receptor antagonist (IL-1Ra), IL-1RI and II, IL-1R accessory protein (IL-1RAcP) and IL-1beta converting enzyme (ICE) was studied by immunocytochemistry, immunoblotting, ELISA and RT - PCR. Cell proliferation was evaluated by [3H]thymidine incorporation, cell fusion by flow cytometry and cell death by in situ end-labelling. Human normal myogenic cells constitutively produced IL-1beta and ICE, with a maximum expression at time of cell fusion. IL-1Rs and IL-1RAcP expression reached a peak at time of commitment to fusion. Myogenic cells produced small amounts of IL-1Ra at latest stages of culture, and only the intracellular isoform. Exposure of cultures to exogenous IL-1beta (1-5 ng/ml) induced myogenic cell apoptosis, without effect on cell proliferation or fusion. IL-1beta-induced cell death was associated with morphological changes including spreading appearance of cells and alteration of cell alignment. We conclude that (1) human myogenic cells constitutively produce IL-1beta; (2) IL-1 system components are differentially expressed during in vitro myogenesis; (3) IL-1 system participates to the coordinated regulation of cell density during normal myogenesis, which could serve to control the muscle mass in vivo.

Human herpesvirus 8 infection in patients with POEMS syndrome-associated multicentric Castleman's disease

The polyneuropathy, organomegaly, endocrinopathy, M protein, skin changes (POEMS) syndrome is a rare multisystemic disorder associated with osteosclerotic myeloma and multicentric Castleman's disease (MCD). Human herpesvirus type 8 (HHV-8) DNA sequences have been detected in lymph nodes of about 40% of human immunodeficiency virus (HIV)-negative patients with MCD, and in bone marrow stromal cells of patients with multiple myeloma. Considering these data, we investigated the presence of HHV-8 in 18 patients with POEMS syndrome (9 with MCD), by nested polymerase chain reaction (N-PCR) to detect DNA sequenses in various cells and tissues obtained by biopsy or at autopsy (13 patients, of whom 7 had MCD), and by an immunofluorescence assay to detect anti-HHV-8 IgG antibodies in blood (18 patients, of whom 9 had MCD). Detection of HHV-8 DNA was performed using three different N-PCR, targeting nonoverlapping regions in open reading frame (ORF) 25 and ORF26. Seven of 13 (54%) POEMS patients had HHV-8 DNA sequences in their tissues, as assessed by all three N-PCR, and 9 of 18 (50%) had circulating anti-HHV-8 antibodies. HHV-8 was mainly detected in the subset of POEMS patients with MCD (6 of 7 [85%] for DNA sequences; 7 of 9 [78%] for antibodies). The percentage of positive N-PCR was higher in lymph nodes than in bone marrow samples (P <.02). Sequencing of amplicons showed a homogeneous restricted variability in the ORF26 region, characteristic of the minority subgroup B defined by Zong, and responsible for isoleucine and glycine substitutions at amino acid positions 134 and 167. These findings strongly suggest an association of HHV-8 infection with POEMS syndrome-associated MCD.

[Macrophagic myofasciitis: description and etiopathogenic hypotheses. Study and Research Group on Acquired and Dysimmunity-related Muscular Diseases (GERMMAD) of the French Association against Myopathies (AFM)]

PURPOSE

A new type of inflammatory myopathy of unknown etiology has recently been described in France. The myopathy, called macrophagic myofasciitis, had never been described in the literature.

METHODS

In December 1998, 35 cases of macrophagic myofasciitis were reported, showing an increase in its incidence since the description of the first case in 1993. The first 22 cases are described.

RESULTS

The 22 patients were each referred with a presumptive diagnosis of either polymyositis (11 patients), polymyalgia rheumatica (5 patients), mitochondrial cytopathy (4 patients), or congenital myopathy or muscle dystrophy (1 patient for each). Clinical symptoms included myalgias (91%), arthralgias (68%), marked asthenia (55%), muscle weakness (45%), and fever (32%). Laboratory findings included elevated CK levels (50%) and a marked increased in the erythrocyte sedimentation rate (37%). Electromyographic recordings showed the existence of myopathy (35%). Muscle biopsy showed a unique pattern characterized by: (i) centripetal infiltration of the epimysium, perimysium and perifascicular endomysium by non epitheloid, cells of the monocyte/macrophage lineage (CD68+, CD1a-, S100-) with both large cytoplasm and PAS-positive content; (ii) absence of necrosis, of both epithelioid and giant cells, and of mitotic figures; (iii) occasional CD8+ T-cells; and, (iiii) minimal myocyte suffering. The disease symptoms were easily distinguishable from those of sarcoid myopathy and fasciitis-panniculitis syndromes. Infectious diseases known to be associated with reactive histiocytosis, including Whipple's disease, Mycobacterium avium intracellulare infection and malakoplakia, could not be documented. Patients' condition improved under corticosteroid therapy, associated or not with non-specific antibiotic therapy.

CONCLUSION

A new inflammatory muscle disorder of unknown etiology, characterized by a distinctive pathological pattern of macrophagic myofasciitis, is emerging in France. Diagnosis is based on muscular biopsy. Numerous clinical, epidemiological and etiopathologic studies initiated by the GERMMAD (Groupe d'études et de recherche sur les maladies musculaires acquises) are in progress.

Neuralgic amyotrophy with phrenic nerve involvement

Phrenic nerve involvement is a rare feature in patients with neuralgic amyotrophy (Parsonage-Turner syndrome). We report four patients who initially presented with severe dyspnea in the absence of lung disease. All patients had a history of infectious disease or surgery and of pain of sudden onset in the shoulder region. Weakness of the proximal arm was observed in only one. Radiographic and pulmonary function studies, phrenic nerve conduction studies, and needle electromyogram (EMG) of the diaphragm documented diaphragmatic paralysis which was unilateral in one patient, bilateral in two patients, and recurrent on alternating sides in another one. Follow-up studies remained abnormal for up to 4 years. Neuralgic amyotrophy with phrenic nerve involvement should be considered in patients presenting with severe, unexplained dyspnea of sudden onset.

Ubiquitin gene expression is increased in human muscle undergoing neurogenic involvement

Histological features of neurogenic muscle involvement included type grouping, muscle fiber atrophy, and target fibers. In muscles with myofiber atrophy and target fibers, we found an increased expression of the genes encoding for the ubiquitin-ATP-dependent proteolytic system. Thus, in patients with target fibers, a 5.2- and a 3.9-fold increase were observed for the 2.4 and 1.2 kb transcripts, respectively, while in those with atrophic angulated hyperoxidative fibers, a 3.9- and a 4.4-fold increase were observed for the 2.4 and 1.2 kb transcripts, respectively. It is suggested that the activation of this proteolytic system may be responsible for the skeletal muscle alterations that often accompany human muscle neurogenic involvement.

Labial salivary gland biopsy for diagnosis of amyloid polyneuropathy

Biopsies of peroneal nerve and labial salivary gland (LSG) were performed in 32 patients with polyneuropathy of unknown origin. Amyloid deposits were detected in 7 LSG (transthyretin=5; amyloid, light chain derived=2) and 6 nerve biopsies. Familial amyloid and light chain amyloid polyneuropathies were subsequently confirmed by relevant tests. We propose that LSG biopsy, a minimally invasive test that may document both sicca syndrome and amyloidosis, should be systematically performed in the investigation of patients with axonal polyneuropathies.

DNA breaks detected by in situ end-labelling in dorsal root ganglia of patients with AIDS

Distal sensory axonal polyneuropathy (DSP) is the most frequent HIV-associated peripheral neuropathy. DSPs tend to occur in full-blown AIDS and worsen as CD4 cell counts decrease in blood. To assess a possible role for apoptosis in the pathogenesis of the neuropathy, we used in situ end-labelling (ISEL) detecting DNA strand breaks in DRG neurons of 19 HIV-infected patients, of whom nine had axonal polyneuropathy, and 11 controls. Sensory neurons with ISEL-assessed DNA breaks were observed in 9/19 patients with AIDS, 0/3 patients with pre-AIDS, and 1/11 controls. The prevalence of DNA breaks in neurons was higher in AIDS patients than in controls (P < 0.05). Among AIDS patients, DNA breaks in neurons were more abundant in patients with peripheral neuropathy (P < 0.04). It is possible that DNA breaks of DRG neurons induce the axonopathy and consequently play a role in the pathogenesis of DSP. It cannot be excluded, however, that DNA breaks could represent the result rather than the cause of axonopathy. We suggest that ISEL may detect neurons that were primed to apoptosis before death in relation with the HIV infection, and undergo DNA fragmentation at time of death, rather than neurons that underwent premortem both priming and triggering steps of the apoptotic process. This hypothesis could explain why most ISEL-positive neurons lack typical apoptotic morphology and why normal controls do not show ISEL positive cells.

Dominant T-cell clones of unknown significance in patients with idiopathic sensory neuropathies

OBJECTIVE

To determine whether idiopathic sensory neuropathies could be associated with circulating dominant T-cell clones, a T-cell equivalent to monoclonal gammopathy of unknown significance.

BACKGROUND

A number of predominantly sensory neuropathies remain of unknown etiology. Circulating dominant T-cell clones may be observed in the elderly, in autoimmune disorders, and in chronic viral infections.

METHODS

Twenty patients with chronic sensory or predominantly sensory neuropathies considered idiopathic after intensive investigation were evaluated for the presence of dominant T-cell clones in blood using PCR amplification of the variable region of the T-cell receptor gamma-chain gene. They were classified as chronic idiopathic axonal polyneuropathy (CIAP) or sensory neuronopathy, i.e., chronic idiopathic ataxic neuropathy (CIAN), according to clinical and electrophysiologic criteria.

RESULTS

Occurrence of clonal expansions of T cells was strikingly high in patients with idiopathic sensory neuropathies (16/20, 80%), with a similar proportion in CIAP (12/15, 80%) and CIAN (4/5, 80%), as compared with elderly normal controls (2/10, 20%), elderly controls with degenerative neurologic diseases (2/10, 20%), and elderly patients with idiopathic chronic inflammatory demyelinating polyneuropathy (2/10, 20%) (all p < 0.005).

CONCLUSION

Both CIAN and CIAP are associated with dominant T-cell clones of unknown significance that cannot simply be attributed to the age of patients. Relevance of T-cell clones to the pathogenesis of idiopathic sensory neuropathies remains to be determined.

Macrophagic myofasciitis: an emerging entity. Groupe d'Etudes et Recherche sur les Maladies Musculaires Acquises et Dysimmunitaires (GERMMAD) de l'Association Française contre les Myopathies (AFM)

BACKGROUND

An unusual inflammatory myopathy characterised by an infiltration of non-epithelioid histiocytic cells has been recorded with increasing frequency in the past 5 years in France. We reassessed some of these cases.

METHODS

We did a retrospective analysis of 18 such cases seen in five myopathology centres between May, 1993, and December, 1997. The myopathological changes were reassessed at a clinopathology seminar.

FINDINGS

Detailed clinical information was available for 14 patients. The main presumptive diagnoses were polymyositis and polymyalgia rheumatica. Symptoms included myalgias in 12 patients, arthralgias in nine, muscle weakness in six, pronounced asthenia in five, and fever in four. Abnormal laboratory findings were occasionally observed, and included raised creatine kinase concentrations, increased erythrocyte sedimentation rate, and myopathic electromyography. Muscle biopsy showed infiltration of the subcutaneous tissue, epimysium, perimysium, and perifascicular endomysium by sheets of large macrophages, with a finely granular PAS-positive content. Also present were occasional CD8 T cells, and inconspicuous muscle-fibre damage. Epithelioid and giant cells, necrosis, and mitotic figures were not seen. The images were easily distinguishable from sarcoid myopathy and fasciitis-panniculitis syndromes. Whipple's disease, Mycobacterium avium intracellulare infection, and malakoplakia could not be confirmed. Ten patients were treated with various combinations of steroids and antibiotics; symptoms improved in eight patients, and stabilised in two.

INTERPRETATION

A new inflammatory muscle disorder of unknown cause, characterised by a distinctive pathological pattern of macrophagic myofasciitis, is emerging in France.

Ubiquitin and proteasome gene expression is increased in skeletal muscle of slim AIDS patients

Human biopsies obtained from skeletal muscle of cachectic AIDS patients clearly showed an increased expression (in relation to that of healthy subjects) of the genes encoding for the ubiquitin-ATP-dependent proteolytic system. Increases of 120% and 42% were observed for the 2.4 and 1.2 kb ubiquitin transcripts, respectively. The expression of the C8 proteasome subunit was also increased by 60% in the cachectic AIDS patients in relation to the healthy control subjects. It is suggested that the activation of this proteolytic system (possibly via changes in circulating cytokines, such as TNF) may be responsible for the skeletal muscle waste that often accompanies AIDS.

Neuropathy in diffuse infiltrative lymphocytosis syndrome: an HIV neuropathy, not a lymphoma

OBJECTIVE

To determine whether CD8 lymphoid infiltrates in nerves of patients with HIV-associated diffuse infiltrative lymphocytosis syndrome (DILS) corresponds to a lymphomatous neoplastic process or to a proliferation of T cells reactional to HIV.

BACKGROUND

DILS is characterized by persistent CD8 hyperlymphocytosis and multivisceral CD8 T-cell infiltration, which may affect peripheral nerves.

METHODS

Presence of monoclonal T cells and HIV-1 proviral load were evaluated by polymerase chain reaction (PCR) techniques in frozen peripheral nerve samples from six patients with DILS neuropathy and 22 patients with other HIV-associated peripheral neuropathies, including mononeuritis multiplex (MM:6), inflammatory demyelinating polyneuropathies (IDP:6), distal sensory polyneuropathy (DSP:5), and toxic distal sensory polyneuropathy (TDSP:5).

RESULTS

Five of six patients with DILS showed no detectable monoclonal T-cell clones in their nerves. Nerve proviral load in DILS (6.8 +/- 0.2 log/10(5) cells) was much higher than in MM (p < 0.008), IDP (p < 0.001), DSP (p < 0.001), and TDSP (p < 0.005).

CONCLUSIONS

DILS neuropathy represents a separate entity among HIV-associated neuropathies. It is associated with massive HIV proviral load in nerve and must not be confused with a peripheral nerve T-cell lymphoma.

[Cytokines and peripheral neuropathies]

Cytokines are polypeptides produced by various cells, with key-roles in regulation of immune response, inflammation and hematopoiesis. Cytokine-producing cells in peripheral nerve include resident and recruited macrophages, lymphocytes, and likely mastocytes, Schwann cells, and probably neurons. Cytokines are instrumental in pathogenesis of peripheral neuropathies during nerve lesions and tissue repair. Tumor necrosis factor-alpha (TNF-alpha) injection into nerve induces Wallerian degeneration. In contrast, interleukin-1 (IL-1) promotes detersion by scavenger macrophages, and increased synthesis of neurotrophic factor (nerve growth factor--NGF--and leukemia inhibitory factor--LIF). Neurotrophic cytokines IL-6, LIF and transforming growth factor-beta 1 (TGF-beta 1) are overexpressed in nerve after experimental axotomy and promote axonal growth until axon/Schwann cell contact. In the course of inflammatory demyelinating neuropathies, proinflammatory cytokines induce vascular permeability and breakdown of blood nerve barrier (TNF-alpha, vascular endothelial growth factor/vascular permeability factor--VEGF/VPF), favor leukocyte transmigration into nerve, induce activation and proliferation of lymphocytes (IL-1, IL-2) and macrophages (gamma-interferon--IFN-gamma), and have a direct myelinotoxic activity (TNF-alpha and TNF-beta). In addition, the inflammatory process is likely favored by downregulation of the anti-inflammatory cytokine TGF-beta 1.

Pulmonary hypertension in POEMS syndrome: a new feature mediated by cytokines

POEMS (polyneuropathy, organomegaly, endocrinopathy, monoclonal gammopathy, and skin changes) syndrome is a rare variant of plasma cell dyscrasia with multiple systemic manifestations. We followed the progress of 20 patients with POEMS syndrome in our institution over a 10-yr period. Pulmonary hypertension (PH) was observed in five patients. All patients suffered dyspnea on exertion, which always appeared during an exacerbation of POEMS syndrome. The typical echocardiographic signs of PH were observed in all of these patients, and the median pulmonary-artery systolic pressure was 57 mm Hg (range, 50 to 65 mm Hg). Mean pulmonary-artery pressure during right side heart catheterization in two patients was 32 mm Hg. No other explanation for the PH could be found. Overproduction of cytokines was found in all cases, with high serum concentrations of interleukin-1beta, interleukin-6, tumor necrosis factor-alpha, and vascular endothelial growth factor. We suggest that PH should be added to the list of symptoms of POEMS syndrome. Cytokines may mediate POEMS syndrome-associated PH, as proposed for the other systemic manifestations of this disorder.

[Muscular complications in HIV infection]

Skeletal muscle involvement may occur at all stages of HIV-infection and represents the first manifestation of the disease into some patients. We usually classify muscle involvement in HIV-infected patients in one of the following categories: HIV-associated myopathy, a myopathy that meets the criteria for polymyositis in a majority of patients, and those for acquired nemaline myopathy in some cases (1); zidovudine myopathy, a reversible mitochondrial myopathy (2); HIV-wasting syndrome and other AIDS-associated cachexias (3); opportunistic infections and tumor infiltrations of the skeletal muscle (4); vasculitic processes and iron pigment deposits (5); HIV-associated myasthenia gravis (6) and rhabdomyolysis (7). Immunohistology for major histocompatibility complex class I antigen and histochemical reaction for cytochrome coxidase are helpful in the correct classification of a myopathy as HIV polymyositis or zidovudine myopathy.

[Central nervous system lesions in the early stages of HIV infection]

Early HIV-1 invasion of the central nervous system has been demonstrated by many cerebrospinal fluid studies; however, most HIV-1 carriers remain neurologically unimpaired during the so-called "asymptomatic" period lasting from seroconversion to symptomatic AIDS. Therefore, very few neuropathological studies have been conducted in the early pre-AIDS stages, and the natural history of central nervous system changes in HIV-1 infection remains poorly understood. Examination of brains of asymptomatic HIV-1 positive individuals who died accidentally and of rare cases with acute fatal encephalopathy revealing HIV infection, and comparison with experimental simian immunodeficiency virus and feline immunodeficiency virus infections suggest that, invasion of the CNS by HIV-1 occurs at the time of primary infection and induces an immunological process in the central nervous system. This includes an inflammatory T-cell reaction with vasculitis and leptomeningitis, and immune activation of brain parenchyma with increased number of microglial cells, upregulation of major histocompatibility complex class II antigens and local production of cytokines. Myelin pallor and gliosis of the white matter are usually found and are likely to be the consequence of opening of the blood-brain barrier due to vasculitis; direct damage to oligodendrocytes by cytokines may also be involved. These white matter changes may explain, at least partly, the early cerebral atrophy observed, by magnetic resonance imaging, in asymptomatic HIV-1 carriers. In contrast, cortical damage seems to be a late event in the course of HIV-1 infection. There is no significant neuronal loss at the early stages of the disease, no accompanying increase in glial fibrillary acid protein staining in the cortex, and only exceptional neuronal apoptosis. Although HIV-1 proviral DNA may be demonstrated in a number of brains, viral replication remains very low during the asymptomatic stage of HIV-1 infection. This makes it likely that, although opening of the blood brain barrier may facilitate viral entry into the brain, specific immune responses including both neutralising antibodies and cytotoxic T-lymphocytes, continuously inhibit viral replication at this stage.

[Neuronal apoptosis in the central and peripheral nervous system in HIV infection]

Apart from the unique changes characteristic of "HIV encephalitis", the productive infection of central nervous system by HIV, which predominantly involves the white matter and basal ganglia, evidence is accumulating that the cerebral cortex may also be affected in AIDS patients. Neuronal loss, suspected at microscopic examination, has been demonstrated by a number of morphometric studies. However, the cause and mechanism of neuronal damage in HIV infection, are still unclear. In an attempt to look for an apoptotic process at the origin of neuronal loss in AIDS, we examined samples of frontal cortex, temporal cortex and basal ganglia from 12 patients who died from AIDS and 4 asymptomatic HIV-positive cases using in situ end labelling to demonstrate characteristic DNA fragmentation. These were compared with 5 asymptomatic seronegative controls, and 2 seronegative patients with Alzheimer's disease. We demonstrated neuronal apoptosis in all AIDS cases and in the Alzheimer's cases. Positive in situ end labelling was usually associated with morphological changes suggestive of neuronal apoptosis. Semiquantitative assessment of the density of apoptotic neurons showed that neuronal apoptosis was more severe in atrophic brains. In contrast, no correlation was found between the density of apoptotic neurons and the presence of HIV-encephalitis or a history of cognitive disorder. Only occasional apoptotic neurons were found in one asymptomatic, HIV-positive case. Apoptosis was never observed in asymptomatic seronegative cases. We also looked for apoptotic neurons in spinal ganglia of 20 AIDS cases, 5 of whom had a terminal sensory distal neuropathy, and 10 seronegative controls devoid of neuropathy. Apoptotic neurons were found in 6 of the AIDS patients and in none of the seronegative controls. However, no correlation was found between the severity of neuronal apoptosis in the spinal root ganglia and the presence of absence of a terminal distal sensory neuropathy. Experimental studies tend to support our in vivo findings. HIV-infection of primary cultures of human embryonic central nervous system induced frequent apoptosis of neurons. No apoptotic cell was identified in non infected control cultures.

[Central nervous system infection due to varicella and zoster virus in AIDS]

We have reviewed 23 cases of varicella-zoster virus infection of the central nervous system in patients with the acquired immunodeficiency syndrome, previously reported in the literature, including 11 from our own series. This allowed us to identify 5 clinico-pathological patterns which could occur simultaneously. In most cases, viral proteins or viral genome were identified using immunocytochemistry or in situ hybridization. Multifocal encephalitis involves predominantly the white matter and is likely to be due to haematogenous spread of the infection. Ventriculitis may have variable appearance according to the course of the disease. In one incipient case, the ependymal lining appeared irregular with foci of infected ependymal cells some of which protruded into the ventricular lumen; in other instances, there was acute or chronic necrosis of the ventricular wall with marked vasculitis. Acute haemorrhagic meningo-myelo-radiculitis with necrotising vasculitis may be associated with ventriculitis and results from shedding of infected ependymal cells into the ventricular lumen and secondary seeding of the cerebrospinal fluid. Focal necrotising encephalitis or myelitis usually follows cutaneous herpes zoster in the corresponding dermatoma and is considered to result from neural spread from the diseased trigeminal or dorsal root ganglion. Vasculopathy involving leptomeningeal arteries and causing cerebral infarcts is associated with meningitis in most cases. These findings are in keeping with the observation in other immunocompromised patients, that varicella-zoster virus spread to the central nervous system may follow different routes. Our study tends to show that varicella-zoster virus infection of the central nervous system is more frequent in the acquired immunodeficiency syndrome than previously suspected and suggests this diagnosis must be considered systematically in cases of encephalitis, ventriculitis, focal myelitis, acute myeloradiculitis and cerebral infarcts in these patients, since an efficient treatment is available.

Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes

Friedreich ataxia is a progressive neurodegenerative disorder caused by loss of function mutations in the frataxin gene. In order to unravel frataxin function we developed monoclonal antibodies raised against different regions of the protein. These antibodies detect a processed 18 kDa protein in various human and mouse tissues and cell lines that is severely reduced in Friedreich ataxia patients. By immunocytofluorescence and immunocytoelectron microscopy we show that frataxin is located in mitochondria, associated with the mitochondrial membranes and crests. Analysis of cellular localization of various truncated forms of frataxin expressed in cultured cells and evidence of removal of an N-terminal epitope during protein maturation demonstrated that the mitochondrial targetting sequence is encoded by the first 20 amino acids. Given the shared clinical features between Friedreich ataxia, vitamin E deficiency and some mitochondriopathies, our data suggest that a reduction in frataxin results in oxidative damage.

All-trans retinoic acid in relapsing malignant gliomas: clinical and radiological stabilization associated with the appearance of intratumoral calcifications

PURPOSE

To evaluate the therapeutic effect of all-trans retinoic acid (ATRA) with and without cytosine arabinoside in relapsing malignant gliomas.

PATIENTS AND METHODS

9 patients (8 male, 1 female, age 53.9 +/- 11.2) with relapsing malignant gliomas (grade IV:6; grade III:3) were treated by ATRA 1 to 21 months after the end of their initial treatment. ATRA was given unceasingly during 2 to 17 months at 90 mg/d. In 6 patients it was associated to cytosine arabinoside (4 g/course, 1 to 9 courses every 4 weeks).

RESULTS

4 non-responder patients died 2.5 to 4 months after starting therapy. One patient who had been reoperated before receiving ATRA and cytosine arabinoside (5 course) had no sign of tumor recurrence after 17 months of treatment. In 4 responder patients (2 glioblastoma and 2 anaplastic astrocytoma) a clinical and radiological stabilization (time to progression) during 9 +/- 2.5 months was observed. This stabilization was associated in 3 of them with the appearance of intra tumoral calcifications visualized on repeated CT scans and confirmed in one patient by post-mortem examination. All of them had received cytosine arabinoside (1 to 9 courses) with ATRA; however small calcifications were also observed in one non-responder patient who did not receive aracytine.

CONCLUSION

These results suggest: a) a therapeutic effect of ATRA in combination with cytosine arabinoside in patients with relapsing malignant gliomas b) that intratumoral calcifications are related to the effects of ATRA on differentiation and/or on endothelial t-PA production and that these effects explain the tumor progression arrest in responder patients. The transient efficiency is probably related to the pharmacokinetics of ATRA or to changes of cellular mechanisms that modulate the cell response to the drug and is a critical issue for this therapy.

Interleukin-1 expression in normal motor endplates and muscle fibers showing neurogenic changes

Histological features of neurogenic muscle involvement include type grouping, muscle fiber atrophy and target fibers. In zidovudine-induced myopathy and dermatomyositis, immunoreactivity for interleukin (IL)-1 has been reported in diseased muscle fibers involving myofibrillar breakdown and atrophy. Since IL-1 is a signal for muscle proteolysis, we studied myofiber expression of IL-1 in neurogenic muscle involvement, specially in atrophic myofibers and target fibers which are associated with myofilament breakdown. Muscle biopsy samples from patients with normal (5 cases) or neurogenic muscle involvement (25 cases) were studied by enzyme histochemistry and immunohistochemistry. In normal muscles, immunoreactivity for IL-1beta was restricted to the postsynaptic domain of motor endplates and that for IL-1alpha had a similar localization but was faint. Immunoreactivity for IL-1alpha and -beta was observed, respectively, in 42.5% and 75.5% of target fibers, in 8.5% and 10.4% of dark angulated fibers, in 0% and 0.3% of non-atrophic type-grouped fibers, in 14.2% and 16.5% of moderately atrophic fibers, and in 65% and 20.9% of severely atrophic fibers. Immunoblot study showed the presence of both proIL-1 (31 kDa) and mature IL-1 (17.5 kDa). From this study, we conclude that IL-1 is normally expressed in the muscular domain of neuromuscular junctions; that IL-1 is mainly expressed in neurogenic target fibers; and that IL-1 expression by muscle fibers in pathological conditions seems to be associated with myofibrillar protein breakdown and regeneration.

Interleukin (IL)-1 beta and IL-1 beta mRNA expression in normal and diseased skeletal muscle assessed by immunocytochemistry, immunoblotting and reverse transcriptase-nested polymerase chain reaction

To confirm the production of IL-1 beta and to optimize detection and semiquantitation of IL-1 beta mRNA by polymerase chain reaction (PCR) techniques in skeletal muscle tissue, immunocytochemistry, immunoblotting and several procedures of RNA extraction and reverse transcription (RT)-PCR amplification were used on muscle samples from 12 patients with conditions associated with local production of IL-1 beta (AZT myopathy: 6 patients; sarcoid myopathy: 6 patients) and from 9 patients with normal muscle used as controls. Abundant IL-1 beta immunoreactivities, corresponding to both pro IL-1 beta and mature IL-1 beta as assessed by immunoblotting, were observed in all diseased muscles, either in inflammatory cells (sarcoid myopathy) or in atrophic muscle fibers (AZT myopathy). Acid guanidinium isothiocyanate phenol-chloroform extraction of RNA appeared less efficient for IL-1 beta mRNA detection by RT-PCR than proteinase K digestion followed by phenol-chloroform extraction. Even using the latter procedure, RT-single PCR for IL-1 beta mRNA was puzzlingly negative in all cases but one; in contrast, RT-nested PCR specified by DNA enzyme immunoassay yielded detection of IL-1 beta mRNA in all diseased muscles and in occasional controls, including the expected PCR product of 391 bp, but also another product of 935 bp, corresponding to IL-1 beta mRNA with unsplicing of the fourth intron. Semi-quantitative PCR showed that production of IL-1 beta mRNA was higher in sarcoid myopathy than in AZT myopathy, and in AZT myopathy than in controls. In conclusion, IL-1 beta expression can be reliably studied using immunocytochemistry, but assessment of IL-1 beta mRNA production in muscle tissue requires optimized extraction and RT-PCR procedures.

Interleukin-1 expression in inflammatory myopathies: evidence of marked immunoreactivity in sarcoid granulomas and muscle fibres showing ischaemic and regenerative changes

The most frequent autoimmune adult inflammatory myopathies are dermatomyositis, polymyositis, inclusion body myositis, and sarcoid myopathy. Interleukin-1 (IL-1) is a pleiotropic molecule, implicated in the inflammatory process, but also in tissue protection and remodelling. We evaluated the immunocytochemical expression of [L,-1alpha and beta in frozen muscle biopsy specimens from patients with dermatomyositis (15 cases), polymyositis (five cases), inclusion body myositis (five cases) and sarcoid myopathy (five cases). Positive immunoreactivities, were observed in both inflammatory cells and muscle fibres. Specificity of the immunostaining was assessed by Western blot experiments. IL-1 positive inflammatory cells were rare in polymyositis and inclusion body myositis, moderately abundant in dermatomyositis, and prominent in sarcoid myopathy granulomas. In sarcoid myopathy, 24.6 +/- 4.1% inflammatory cells were IL-1alpha-positive and 45.2 +/- 2.6% were IL-1beta-positive. IL-1 positive muscle fibres were mainly observed in dermatomyositis, usually remote from inflammatory infiltrates. Positive immunostaining for IL-1 was observed in fibres showing ischaemic punched-out vacuoles, that correspond to areas of myosinolysis, in atrophic perifascicular fibres, and in fibres located within healing microinfarcts. All NCAM-positive regenerating fibres were IL-1 positive. We conclude that: (i) IL-1 is expressed in granulomas of sarcoid myopathy, which is in keeping with the role ascribed to IL-1 in the formation of granulomas: (ii) IL-1 is expressed by muscle fibres undergoing ischaemic damage: and (iii) IL-1 expression by muscle fibres is associated with myofibrillar protein breakdown and regeneration.

Peripheral neuropathy in human immunodeficiency virus-infected patients with the diffuse infiltrative lymphocytosis syndrome

A subset of human immunodeficiency virus (HIV)-infected patients develop persistent CD8 hyperlymphocytosis and a Sjogren's syndrome-like syndrome associated with multivisceral CD8 T-cell infiltration, known as the diffuse infiltrative lymphocytosis syndrome (DILS). Patients with DILS tend to have higher CD4 cell counts, fewer opportunistic infections, and longer survival times than other HIV-infected patients. Peripheral nerve involvement in DILS has been poorly documented. We studied 12 HIV-infected patients with CD8 hyperlymphocytosis, DILS, and clinical signs of peripheral neuropathy. Two of 4 patients who were HLA typed were HLA-DR5 and 1 was HLA-DR6. All patients had the sicca syndrome and multivisceral involvement. The neuropathy was acute or subacute, always painful, and symmetrical in 8 cases. Electrophysiology was consistent with axonal neuropathy in 10 of 12 patients. Nerve biopsy showed marked angiocentric CD8 infiltrates without mural necrosis (12 of 12), and abundant expression of HIV p24 protein in macrophages (12 of 12). The HIV genome was detected by polymerase chain reaction in nerve homogenates. Zidovudine therapy was associated with improvement in 6 of 6 patients and steroid therapy was beneficial in 4 of 5 patients. No T-cell lymphoma was observed during follow-up, but 2 patients developed a primary B-cell lymphoma. We conclude that DILS neuropathy represents HIV-associated neuropathy, characterized by marked CD8 infiltration and abundant HIV in nerve, that improves with zidovudine or steroid therapy, and probably reflects a systemic host-determined and antigen-driven response to HIV.