Nontropical Pyomyositis in an Immunocompetent Host

Pyomyositis of the pectineus muscle in an adolescent male

The 'irritable hip' continues to pose a challenge for clinicians. Even with predictive clinical algorithms, decision making can be difficult. Emergency treatment is required if septic arthritis is suspected. Other differential diagnoses such as transient synovitis, pyomyositis of the pelvic girdle muscles and osteomyelitis must be considered in order to help guide appropriate investigations and allow early treatment. We report the case of a 13-year-old boy presenting to our institution with an acutely painful left hip but still able to weight bear. Despite a fever and raised inflammatory markers, the clinical examination did not correspond to that of an infected hip joint. Urgent magnetic resonance imaging (MRI) confirmed pyomyositis of the pectineus muscle. To our knowledge, this is the first reported case in the literature. The child was treated with seven days of intravenous antibiotics. There was a good clinical response as well as normalisation of the C-reactive protein level and white cell count. The patient was discharged home with a further week of oral antibiotics. Follow-up MRI at two weeks demonstrated a dramatic reduction in the inflammation of the pectineus. At the clinic follow-up appointment, the child was asymptomatic and back to normal function. Pyomyositis is typically found in tropical areas but its rates in temperate climates have been rising. It usually affects large groups of muscles such as the quadriceps and gluteal muscles. MRI is the gold standard investigation. If diagnosed early, the condition can be treated successfully with intravenous antibiotics alone. Given the widespread availability of MRI, we recommend its increased use to distinguish between pyomyositis and other paediatric hip pathologies.

Primary obturator internus and obturator externus pyomyositis

Background

Pyomyositis is a rare condition in immune competent patients and is usually seen in tropical countries. Pyomyositis of obturator muscles in particular is an extremely rare condition, which causes hip pain and mimics septic arthritis.

Case Report:

This is a case report of a 9-year-old boy without an underlying disease or a compromised immune system, who presented with knee pain that progressed to hip pain and inability to bear weight. He was diagnosed initially with septic arthritis of the hip and underwent unnecessary hip exploration surgery. Magnetic resonance imaging scan was performed postoperatively and showed pyomyositis of obturator internus and obturator externus muscles. He was managed medically and had a good outcome.

Conclusions:

A greater awareness of this emergency condition is necessary to prevent misdiagnosis, unnecessary surgical intervention, and to avoid the devastating possible complications of delayed diagnosis.

Primary obturator-muscle pyomyositis in immunocompetent children

PURPOSE

Primary pyomyositis in immunocompetent children in non-tropical regions (countries with temperate climates) is very uncommon. It is rarely found in the intrapelvic muscles, and even more rarely in the obturator muscles. We try to draw attention to the potential occurrence in these conditions.

METHODS

Five new cases of primary obturator-muscle pyomyositis in immunocompetent children aged between 6 and 11 years in a temperate climate are presented. They present with symptoms as follows: fever, pain (thigh, abdominal, inguinal, and/or hip pain), and limp. Three of them had no hip movement limitation. All of them had tenderness in the perineum zone.

RESULTS

Laboratory tests may reveal high erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) counts, but depend on the length of diagnostic delay. The evolution time oscillated from 1 to 5 days. Fever and limp disappearance depends on the evolution time previous to the onset of the antibiotics administration. In 4 out of 5 patients, Staphylococcus aureus was present in the blood cultures. In all cases of obturator-muscle pyomyositis, diagnosis was confirmed using computed tomography (CT) scan (one) and/or magnetic resonance imaging (MRI) (four).

CONCLUSIONS

Obturator-muscle pyomyositis is aimed at emphasizing the diagnostic difficulties associated with the condition, due to its deep location and to the fact that the disease presents with multiple manifestations that may initially cause confusion, since they mimic other conditions occurring in the abdomen, hip (septic arthritis, osteomyelitis), spine, etc. The diagnosis is only confirmed using CT scan and/or MRI. In the five patients with antibiotics treatment, the condition resolves without sequelae, even at long-term follow-up.

Gluteal pyomyositis in a non-tropical region as a rare cause of sciatic nerve compression: a case report

INTRODUCTION

Pyomyositis, or isolated abscess formation within a skeletal muscle, is a relatively common condition in tropical climates but it is only encountered rarely in temperate zones.

CASE PRESENTATION

We present a case of non-tropical pyomyositis of the gluteal muscle in a 26-year-old, previously healthy man from the United Kingdom, who initially presented with sciatica-like symptoms which began 3 days after a mosquito bite on his nose, which had become infected and discharged pus.

CONCLUSION

Gluteal pyomyositis involving the sciatic nerve may initially present as radiculopathy. Mosquito bites may have been the source of transient bacteraemia that contributed to muscle suppuration in this patient. This may explain, at least in part, the increased incidence of pyomyositis in healthy individuals living in tropical regions.

Primary pyomyositis of the paraspinal muscles: a case report and literature review

A case of non-tropical pyomyositis in a healthy, adolescent, 13-year-old boy, affecting the paraspinal muscles is presented. Computerised axial tomography scan (CT scan) of the spine provided valuable information on the nature, extent of the disease and helped to plan successful surgical management. None of the reported cases of such severity of paraspinal pyomyositis had involvement of quadratus lumborum muscle or compression on retroperitoneal organ as in our case.