Pneumococcal pyomyositis

Pyomyositis associated with abscess formation caused by streptococcus pneumoniae in children: a case report and review of literature

BACKGROUND

Pyomyositis is an unusual bacterial infection but potential severe in children. Staphylococcus Aureus is the main caused of this disease (70-90%), following by Streptococcus Pyogenes (4-16%). Streptococcus Pneumoniae rarely caused invasive muscular infections. We describe a case of pyomyositis caused by Streptococcus Pneumonia in an adolescent 12-year-old female.

CASE PRESENTATION

I.L. referred to our hospital for high fever associated with right hip and abdominal pain. The blood exams showed increase of leukocytes with prevalence of neutrophils with high level of inflammatory markers (CRP 46,17 mg/dl; Procalcitonin 25,8 ng/ml). The abdomen ultrasonography was unremarkable. The CT and MRI of the abdomen and right hip revealed pyomyositis of the iliopsoas, piriformis and internal shutter associated with collection of pus between the muscular planes (Fig. 1). The patient was admitted to our paediatric care unit, and she was initially treatment with intravenous Ceftriaxone (100 mg/kg/day) and Vancomycin (60 mg/kg/day). On day 2, a pansensitive Streptococcus Pneumoniae was isolated from the blood culture, and the antibiotic treatment was changed to only IV Ceftriaxone. She was successively treated with IV Ceftriaxone for 3 weeks, then continued with oral Amoxicillin for a total of 6 weeks of therapy. The follow up showed a complete resolution of the pyomyositis and psoas abscess after 2 months.

CONCLUSION

Pyomyositis associate with abscess is a rare and very dangerous disease in children. The clinical presentation can mimic symptoms of other pathologies like osteomyelitis or septic arthritis, so many times is hard to identify. The main risk factors include story of recent trauma and immunodeficiency, not present in our case report. The therapy involves the antibiotics and, if possible, abscess drainage. In literature there is much discussion about duration of antibiotic therapy.

Infective myositis

Myositis is inflammation especially of the voluntary muscles, characterized by localized or diffuse pain, tenderness on movement or palpation, swelling, and/or weakness. The two main categories of myositis include non-infectious and infectious. Infective myositis may be due to a wide variety of pathogens, including bacteria, fungi, viruses, and parasites. A brief account of the various pathogens causing infective myositis is discussed.

Osteoarticular Infections Caused by Streptococcus pneumoniae in Children in the Post-Pneumococcal Conjugate Vaccine Era

BACKGROUND

Pneumococcal osteoarticular infections (OAIs) are an uncommon manifestation of invasive pneumococcal disease (IPD). We describe the demographic characteristics, hospitalization rate, serotype distribution and antibiotic susceptibility of children with pneumococcal OAI over a 16-year period.

METHODS

We identified patients ≤18 years old with pneumococcal OAI at 8 children's hospitals in the United States (2000-2015). Pneumococcal isolates were collected prospectively. Serotyping and antibiotic susceptibility were performed in a central laboratory.

RESULTS

We identified 97 (3.3%) patients with pneumococcal OAI out of 2943 patients with IPD. Over 60% of the children were <2 years old. Septic arthritis (56.7%, 55/97) was the most common pneumococcal OAI, followed by osteomyelitis (25.8%, 25/97) and septic arthritis with concomitant osteomyelitis (17.5%, 17/97). Hospitalization for pneumococcal OAI overall decreased from 6.8 [95% confidence interval (CI): 5.2-8.6] to 4.4 (95% CI: 3.0-6.3) per 100,000 admissions from 2000-2009 to 2010-2015 (-35%, P = 0.05). Hospitalization for pneumococcal OAI caused by PCV13 serotypes decreased from 4.6 (95% CI: 3.4-6.2) to 0.9 (95% CI: 0.3-1.9) per 100,000 admissions from 2000-2009 to 2010-2015 (-87%, P < 0.0001). Overall, 12% of isolates had a penicillin minimal inhibitory concentration> 2 µg/mL, 3% a ceftriaxone minimal inhibitory concentration> 1 µg/mL and 15% were clindamycin resistant; these proportions remained unchanged after the introduction of PCV13. Serotypes 19A and 35B were responsible for penicillin and ceftriaxone nonsusceptible isolates in 2010-2015.

CONCLUSIONS

Pneumococcal OAI represents 3% of all IPD, affecting mainly healthy infants and young children. Hospitalization for pneumococcal OAI caused by PCV13 serotypes dramatically decreased (-87%) after the introduction of PCV13.

Pneumococcal pyomyositis: report of 2 cases and review of the literature

Streptococcus pneumoniae is an uncommon cause of pyomyositis. It is unclear whether the clinical presentation and outcome of pneumococcal pyomyositis differ depending on the host's underlying immune status. We describe 2 patients with pneumococcal pyomyositis, review all published cases, and compare characteristics between apparently healthy hosts and at-risk hosts. A total of 35 cases of pneumococcal pyomyositis were identified, 11 in apparently healthy hosts and 24 in at-risk hosts. Two-thirds of the patients had an antecedent respiratory illness or meningitis. At-risk hosts tended to have a longer interval between the development of symptomatic muscle infection and the diagnosis of pyomyositis and a significantly higher risk of disseminated disease at presentation, as manifested by involvement of multiple noncontiguous muscles or presence of meningitis. Overall, other than 1 death, all patients recovered with antibiotics and surgical drainage, but as might be expected there was a significantly higher rate of complications among at-risk hosts.

Pyomyositis due to Streptococcus pneumoniae

Pyomyositis is an unusual but potentially serious disease in children. Staphylococcus aureus is the most commonly implicated pathogen, but pneumococcal pyomyositis is very rare. Clinical diagnosis of pyomyositis can be difficult often mimicking septic arthritis of the hip or appendicitis. We report a 12-year-old male with pyomyositis caused by Streptococcus pneumoniae who presented with fever and severe right hip and abdominal pain. Magnetic resonance imaging of the right hip revealed the diagnosis of pyomyositis. Blood cultures grew Streptococcus pneumoniae, sensitive to penicillin, ceftriaxone, and clindamycin. He was successfully treated with a 3-week course of clindamycin. Early recognition, appropriate antibiotic therapy, and if indicated, drainage of the muscle abscess is critical to reduce morbidity and mortality.

Primary pyomyositis in children: a retrospective analysis of 11 cases

This study was undertaken to review our approach to diagnosis and treatment in a series of 11 patients (mean age 8.2 years) with primary pyomyositis, who had neither an underlying disease nor a compromised immune system. Nine of the children had positive blood cultures, Staphylococcus aureus (eight) and Streptococcus group A (one). The sites of infection were iliopsoas (four), obturator (two), hip adductors (two), levator scapula (one), thoracolumbar paraspinal (one) and gastrocnemius (one) muscles. Antibiotic treatment was initially intravenous, followed by oral administration. Of five patients with evidence of abscess formation, three underwent percutaneous drainage, whereas two required open surgical drainage. The infection resolved completely without any sequela in 10 children. One patient who developed acute compartment syndrome showed late signs of osteonecrosis of the tibial shaft segment.

Pyomyositis: a fatal case in a healthy teenager

Pyomyositis is a common disease in the tropics that is reported with increasing frequency in the United States. We describe an unusually fulminant, fatal case in a previously healthy adolescent male. This case illustrates the clinical progression of pyomyositis from localized muscle infection to disseminated disease, and highlights the importance of considering this rare diagnosis in any stage of occult sepsis.

Pneumococcal psoas pyomyositis associated with complement deficiency

A 4.5-year-old boy with complement deficiency developed infection of the psoas caused by Streptococcus pneumoniae. Pyomyositis of the psoas muscle is uncommon but should be included in the differential diagnosis of fever and lameness. The most useful diagnostic test is computed tomography guided needle aspiration, and underlying conditions should be sought.