Primary obturator-muscle pyomyositis in immunocompetent children

A fatal case of paediatric post-traumatic pyomyositis

A 6-year-old girl was brought to the emergency department with a history of an accidental fall a few days earlier. She presented with a fever, cough and constipation. Sars-CoV-2 infection being suspected, she was transferred to a paediatric facility for Covid-positive patients. During the diagnostic process, the clinical picture suddenly deteriorated with the development of bradycardia, tachypnea and altered sensorium. Despite cardiopulmonary resuscitation attempts, the child died about 16 hours after admission to the emergency department. A judicial forensic autopsy was performed that concluded that her death was due to multiple acute pulmonary, cardiac and renal infarctions secondary to septic thromboembolism in the course of post-traumatic bacterial necrotizing pyomyositis of the right ileo-psoas muscle.

Obturator pyomyositis and labium majus cellulitis: A case report and literature review

Pyomyositis is a rare, subacute, deep bacterial infection of the skeletal muscle. When treatment is delayed, pyomyositis causes abscess formation and progresses to sepsis; therefore, its early diagnosis is important. However, the clinical presentation and laboratory findings of pyomyositis are not specific; hence, diagnosis often takes time. We encountered the case of a girl with obturator pyomyositis and redness and swelling of the labium majus, which we considered as potentially important symptoms for distinguishing obturator pyomyositis from septic hip arthritis. An 8-year-old Japanese girl presented to our hospital with fever and right hip pain. On physical examination, she had redness and swelling of the right labium majus and a right limp. She was diagnosed with obturator pyomyositis and labium majus cellulitis with magnetic resonance imaging. Her clinical presentation markedly improved after starting antibiotic therapy with intravenous cefazolin for 2 weeks and oral cefaclor for 1 week. Improvement in the inflammation of the obturator muscle and labium majus was confirmed with follow-up magnetic resonance imaging. She recovered fully with no long-term sequelae. In conclusion, obturator pyomyositis rather than septic hip arthritis should be considered in children with a limp and hip and perineal pain, particularly girls with redness and swelling of the labium majus. In addition, imaging studies, including magnetic resonance imaging, should be performed for early diagnosis.

Primary Bacterial Pyomyositis in Children: A Systematic Review

BACKGROUND

Tropical pyomyositis has had a recent increase in the United States, Europe, and other nontropical areas. The purpose of this study was to provide an accurate description of the demographics, presenting features, sites of involvement, microbiology, imaging modalities, medical and surgical management, complications, and predictors of clinical course.

METHODS

We searched PubMed, Cochrane, Web of Science Collection, Scopus, and Embase databases yielding 156 studies. Of these, 23 articles were selected for statistical analysis.

RESULTS

The average age at presentation was 8.4±1.9 years with males more commonly affected. Fever, painful limp, and localized pain were the most common presenting symptoms. Pelvis, lower extremity, trunk and spine, in descending order, were the most commonly affected locations. Iliopsoas, obturator musculature, and gluteus musculature were the most commonly affected muscle groups. The mean time to diagnosis was 6.6±3.05 days. Staphylococcus aureus was the most common offending organism. The mean length of hospital stay was 12.0±4.6 days. Medical management alone was successful in 40% of cases (143/361) with an average duration of 9.5±4.0 and 22.7±7.2 days of intravenous and oral antibiotics, respectively. Surgical management consisted of open drainage in 91.3% (199/218) or percutaneous drainage in 8.7% (19/218) of cases. Painful limp, fever, and larger values of white cell count and erythrocyte sedimentation rate were associated with an increased need for surgery. Obturator and calf muscle involvement were strongly associated with multifocal involvement. There were 42 complications in 41 patients (11.3%). Methicillin-resistant S. aureus was associated with an increased risk of complications. The most common complications were osteomyelitis, septicemia, and septic arthritis.

CONCLUSIONS

Primary pyomyositis should be considered in cases suggesting pediatric infection. Magnetic resonance imaging is the most commonly used imaging modality; however, ultrasound is useful given its accessibility and low cost. Medical management alone can be successful, but surgical treatment is often needed. The prognosis is favorable. Early diagnosis, appropriate medical management, and potential surgical drainage are required for effective treatment.

LEVEL OF EVIDENCE

Level IV-systematic review.

Obturator internus and externus muscle abscess caused by methicillin-resistant Staphylococcus aureus in a 6-year-old boy: A case report

Obturator abscess is a rare condition in children which usually occurs commonly in tropical countries. Because of its rarity, vague symptomatology and a lack of focus about this condition, the diagnosis of obturator abscess is commonly delayed or missed. Hence, physicians should be familiar with this condition and have a high index of suspicion when a patient presents with fever, pain in the thigh, hip or abdomen and a limp on the affected side which are considered as the classic clinical triad of obturator abscess. Herein, we present a 6-year-old previously healthy Russian boy who was on holiday in Sri Lanka. He presented on the third day of the fever associated with pain in the right thigh and abdomen. This is the first reported case of an obturator externus muscle abscess due to methicillin-resistant Staphylococcus aureus in a European boy visiting a tropical country.

Obturator externus abscess in a 9-year-old child: A case report and literature review

RATIONALE

Obturator pyomyositis is a rare condition in children. Diagnosis is often delayed because of its rarity, and the vagaries of its presentation cause it to be easily be missed. Physicians should therefore familiarize themselves with this condition and consider it as a possible differential diagnosis in patients presenting with an acutely painful hip. Inflammatory syndrome is also frequent among sufferers and the MRI is a very sensitive diagnostic tool for obturator pyomyositis. Additionally, joint fluid aspirations and blood cultures are also useful in identifying the pathogen. The appropriate antibiotic therapy provides a rapid regression of symptoms during the early stage of pyomyositis. In cases of MRI-confirmed abscess, surgical treatment is indicated.

PATIENT CONCERNS

Our report focuses on a case of obturator pyomyositis in a 9-year-old boy. The child was febrile for 5 days and could only manage to walk a few steps. His hip range of motion was restricted in all directions. In addition, the patient had presented pain and swelling of his right elbow for a day, with a restriction of motion in the joint. There was a clear inflammatory syndrome. A diagnosis of hip and elbow septic arthritis was suspected, and the child underwent joint aspiration of the both cited joints. The aspiration of the elbow returned pus. Conversely, no effusion was found in the hip aspiration. The administration of empiric intravenous antibiotherapy was started.

DIAGNOSES

An MRI revealed an osteomyelitis of the ischio-pubic area associated with a subperiosteal abscess.

INTERVENTIONS

Subsequently, 3 days after elbow arthrotomy, a surgical treatment was performed on the patient's right hip in order to evacuate the subperiosteal abscess and muscular collection because of the persistence of the patient's symptoms and inflammatory syndrome despite susceptible intravenous antibiotics. Postsurgery the patient showed steady improvement.

LESSONS

Such cases demonstrate how diagnosis can be difficult because pelvic pyomyositis is often mistaken for more common pathologies such as septic arthritis, osteomyelitis, or appendicitis. This may delay the diagnosis or refer misdiagnosis. We discuss this rare infection in light of the literature with particular reference to its incidence, clinical features, bacteriological etiology, biological, and radiological presentation, and above all, its treatment.

Pediatric pelvic pyomyositis: initial MRI can be misleading

Pelvic pyomyositis is an infection of the skeletal muscles around the hip joint. Fever, hip pain, limp, and leukocytosis are common; however, the clinical picture is often vague. MRI is the current gold-standard imaging for pyomyositis. No studies in the current literature have reported an unremarkable initial MRI in a patient with symptomatic pyomyositis. An adolescent female presented with symptomatic pelvic pyomyositis, but admission MRI was normal. A follow-up MRI indicated development of pelvic pyomyositis. The patient was successfully managed nonoperatively. The initial MRI in pyomyositis can be misleading. Patients should be admitted and MRI should be repeated, as indicated clinically.

Pyomyositis in Children

Primary pyomyositis in children is prevalent in the tropics and increasingly being recognised from temperate regions. Staphylococcus aureus remains the principle causative organism worldwide, while proportion of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) is on rise. Commonly involved groups are around the pelvis and lower limbs. Clinical presentation depends on the stage of disease, most commonly a child presenting with limping with fever. Early diagnosis and management are crucial. The investigation of choice is MRI scan. Appropriate antibiotic treatment should be instituted at the earliest opportunity along with drainage. Majority of patients show excellent and complete recovery with no long-term complications once treatment is started early. A high level of awareness and suspicion of this condition is warranted from all paediatric clinicians.