Granulomatous interstitial polymyositis and intramuscular neuritis in a dog

Background Granulomatous myositis is a rare condition in both humans and dogs. In humans it is most frequently related to sarcoidosis, where a concurrent granulomatous neuritis has been reported occasionally. Simultaneous granulomatous myositis and neuritis have been diagnosed previously in dogs (unpublished observations), but have not been studied further. Additional investigations are therefore warranted to characterize this disorder. Here we present a detailed description of concurrent idiopathic granulomatous myositis and granulomatous neuritis in a dog with suspected immune-mediated aetiology. Case presentation The dog presented with dysphonia and paresis in the pelvic limbs and tail. In addition to muscle biopsies being taken for histopathology, magnetic resonance imaging, computed tomography and electrodiagnostics were performed. Muscle biopsies displayed granuloma formation with giant cells and epithelioid macrophages in muscle fibres and nerve branches. Microorganisms were not detected. Long-term treatment with glucocorticoids was clinically successful. Two years after the clinical signs started, the dog presented with signs of sepsis and died. Histopathologically, no granulomatous inflammation could be demonstrated in either muscles or nerves at that time. Conclusions This case illustrates a granulomatous interstitial polymyositis and intramuscular neuritis that improved clinically and resolved histologically with glucocorticoid treatment. Idiopathic granulomatous myositis and neuritis should be considered as a differential diagnosis in dogs with clinical signs of neuromuscular disorders.

Contracturing Granulomatous Myositis with Recurrent Malignant Thymoma and Myasthenia Gravis: A Case Report

Contracturing granulomatous myositis (CGM) is a very rare myopathic syndrome where patients present with slowly progressive muscle pain or weakness affecting mainly proximal muscles together with flexion contractures of the limbs. To date, there have only been several case reports of CGM, which have been reported to occur most commonly in association with sarcoidosis. We report a case of CGM associated with recurrent malignant thymoma and myasthenia gravis (MG). A gentleman with history of treated malignant thymoma presented with new onset proximal muscle weakness and pain that later evolved into contractures that persisted despite treatment with steroids and intravenous immunoglobulin. A malignancy workup revealed recurrence of his malignant thymoma warranting chemotherapy treatment. His contractures only resolved after addition of chemotherapy treatment. He later developed clinical features of MG 1 year after his initial elevation in Anti-acetylcholine (Anti-AChR) antibody levels. We postulate CGM to be a paraneoplastic phenomenon of underlying malignant thymoma. Treatment of thymoma together with immunosuppressive therapies led to clinical improvement of our patient’s CGM. The sole elevation of Anti-AChR levels without the accompanying clinical features does not equate to a MG diagnosis, but should raise the clinician’s vigilance for future development of the condition.

Huffmanela spp. (Nematoda: Trichosomoididae) from Orange-spotted Grouper (Epinephelus coioides, Hamilton, 1822) at Jubail Province, on the Arabian Gulf, Saudi Arabia: A case report

This paper is conducted for identifying the parasite which collected during regular routine inspection for the hygienic condition and health status of fish in 2019 at the central fish market shops at Jubail city, Saudi Arabia. Samples from an orange spotted grouper (Epinephelus coioides) fish showed heavy black streaks between the muscle fibers that was considered unmarketable and rejected by the consumer after had been cut and prepared for sealing. The black discolorations were in the form of heavy diffused focal black spots or forming threads of variable sizes embedded in the entire whole-body musculature of the fish. These samples were subjected to parasitological and pathological evaluation. The parasitological examination of the affected muscular tissues revealed Huffmanela spp. eggs infection. The parasitic infestation was identified on the bases of the morphological and ultra-structural characters of the eggs. The histopatholgical investigation of the dark discoloration of the muscular tissues showed severe diffused multifocal granulomatous myositis reactions in the form of chronic inflammatory response accompanied with fibrous connective tissue proliferation around the eggs and larvae together with lymphocytes and macrophages aggregation. Muscular necrosis, edema and evidence of muscular regeneration were also noticed. In conclusion; this case report confirmed the occurrence of Huffmanela spp. infection in the muscles of Epinephelus coioides by using light and scanning electron microscopy.Further molecular assessment is recommended.

O09 Isolated muscular sarcoidosis revealed by calcitriol-mediated hypercalcaemia and fluorodeoxyglucose positron emission tomography

Case report - Introduction Sarcoidosis, a multisystem disorder of unknown aetiology, commonly presents with bilateral hilar adenopathy, pulmonary infiltrates, skin and/or eye lesions. Musculoskeletal and neuromuscular manifestations occur less commonly. Calcitriol-mediated hypercalcaemia is a known complication of sarcoidosis. Severe hypercalcaemia, however, is detected in ˂5% of patients and pseudo-malignant hypercalcaemia (>3.5 mmol/L) is very unusual. There are limited reports of isolated granulomatous myositis causing hypercalcaemia. Our patient uniquely presented with symptoms of hypercalcaemia and PET-scan incidentally revealed sarcoid-like myositis. This case reports an unusual presentation of life-threatening hypercalcaemia revealing sarcoid myositis that rheumatologists and physicians should be aware of. Case report - Case description The patient, a 69-year old Caucasian female, was referred to Rheumatology after a PET-scan identified features of sarcoid myositis. She was initially admitted due to hypercalcaemia and 2 months of tiredness, lethargy, generalised weakness, and nausea. She had difficulty in climbing stairs but was independently mobile with no difficulty standing from sitting. History included biopsy-proven cutaneous lupus (on Hydroxychloroquine, which she stopped weeks prior to admission), chronic interstitial cystitis and CKD stage 3A without proteinuria. Clinical examination was unremarkable. Bloods showed hypercalcaemia (3.62 mmol/L) with inappropriately normal PTH (1.8 qmol/L) and a raised ACE (72 U/L). PET-scan showed symmetric, diffuse, and heterogeneous muscular activity within the posterior thighs, anterior to the hips and psoas muscles, reported as possible sarcoid-like myositis. PET-scan findings were discussed with nuclear medicine team and deemed non-specific. Remaining results included phosphate 1.28, ALP 78, vitamin D3 64, urea 8.6, creatinine 97, e-GFR 49, ESR 10 and CK 30. Normal CXR, CT head and MIBI NM parathyroid scan. CT thorax, abdomen and pelvis showed bladder calcification. Calcium level and symptoms resolved with IV fluid, IV pamidronate and zoledronic acid. She was discharged with follow up arranged. Follow-up bloods revealed high 1,25 vitamin D of 259 (43-144pmol/L) raising the possibility of calcitriol-mediated hypercalcaemia from granulomatous myositis. EMG showed borderline myopathic results. Calcium levels and symptoms remained stable, so no treatment was initiated until 6 months following initial presentation, when she was readmitted with severe hypercalcaemia, similar symptomatology, and normal examination. MRI thighs showed changes consistent with myositis and muscle biopsy revealed granulomatous inflammation consistent with sarcoid. Myositis autoantibodies (anti Ro-52) came back positive. After 10 months of multiple investigations and monitoring, a diagnosis of sarcoid myositis has been made and patient initiated on a Prednisolone tapering regimen; her response is yet to be assessed. Case report - Discussion In patients with granulomatous disease, such as sarcoidosis, hypercalcaemia occurs because of ectopic 25(OH)D-1-hydroxylase expression in macrophages and formation of excessive amounts of 1,25(OH)2D. In a review of 101 adult cases of calcitriol-mediated hypercalcaemia, 48% were eventually diagnosed with sarcoidosis. Sarcoid myositis, as described by Aubart et all, has four patterns: nodular; smouldering phenotype; acute, subacute, or progressive myopathic; and combined myopathic/neurogenic type. In all patterns, sarcoidosis was multi-visceral with a median of 3 extra muscular organs involved (mostly lungs, lymph nodes, eyes, and skin). Our patient, however, did not fit into one of these patterns given her single-organ involvement which is clearly challenging. Furthermore, rather uniquely, our patient had no respiratory symptoms and chest imaging did not reveal hilar lymphadenopathy. It was the PET-scan, performed as part of malignancy screen for resistant hypercalcaemia, which highlighted the diagnosis. However, due to lack of objective weakness on examination and normal CK the significance of this incidental nonspecific finding was deemed low. A literature review has highlighted 12 similar cases where PET-scan, performed as malignancy screening for hypercalcaemia, incidentally, revealed intense, diffuse, and isolated muscular FDG uptake consistent with granulomatous myositis. CK was normal in all cases and no patients displayed the usual thoracic features of sarcoidosis. All patients were treated with high-dose steroids and achieved rapid, complete, and sustained remission. Case report - Key learning points Sarcoidosis should be considered in patients presenting with symptomatic hypercalcaemia with no apparent causes and negative routine workup. The absence of proximal weakness or elevated muscle enzymes do not preclude the diagnosis of granulomatous myositis. Severe hypercalcaemia revealing a diffuse granulomatous disorder limited to muscles might be life threatening and following literature review appears highly steroid-sensitive. We describe a rare case where PET-scan incidentally revealed sarcoid-like myositis features which were subsequently demonstrated by muscle biopsy. Rheumatologists and physicians should be aware of this potential cause of markedly elevated calcium, even with normal CK and CXR and no prior sarcoidosis diagnosis. Earlier recognition of this disease phenotype can avoid unnecessary investigations, diagnosis delay and added stress to patients.

Atypical Multibacterial Granulomatous Myositis in a Horse: First Report in Italy

Infectious causes of myositis are reported relatively uncommonly in horses. Among them, bacterial causes include Streptococcus equi subsp. zooepidemicus, Actinobacillus equuli, Fusobacterium spp. Staphylococcus spp, and Corynebacterium pseudotuberculosis. Infection can be spread to muscles via haematogenous or extension from skin lesions. Parasitic myositis has also been documented. In this report, a 12 year-old Italian Quarter Horse mare presented with diffuse subcutaneous nodules and masses ranging from 2 × 3 to 5 × 20 cm in size, and adherent to subcutis and muscles that were first macroscopically and cytologically diagnosed as pyogranulomas. Subsequently, histological, molecular, bacteriological, and biochemical investigations were performed. All the data obtained allowed to diagnose a severe and diffuse multibacterial granulomatous myositis caused by Corynebacterium pseudotuberculosis and Corynebacterium amycolatum. Following the therapy and an initial disappearance of most of the lesions together with a general improvement of the mare, the clinical condition deteriorated, and new nodules appeared. Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and PCR techniques revealed the presence of bacteria as Glutamicibacter creatinolyticus and Dietzia spp. To the authors’ knowledge, this case report represents the first description of multibacterial granulomatous myositis due to Corynebacterium pseudotuberculosis, Corynebacterium amycolatum, Glutamicibacter creatinolyticus, and Dietzia spp. in a horse reared in Italy.