Journal of Pediatric Surgery Case Reports 19 (2017) 38e40
Contents lists available at ScienceDirect
Journal of Pediatric Surgery Case Reports journal homepage: www.jpscasereports.com
Case report: Primary osteomyelitis of the sternum in a seven-monthold male Anthony Tran, M.D., M.S. a, *, Tariq Lescouflair, M.D. a, Shrey Patel, M.D. a, Richard Weiss, M.D. a, b a b
Department of Surgery, University of Connecticut Health Center, Farmington, CT, USA Department of Pediatric Surgery, Connecticut Children's Medical Center, Hartford, CT, USA
a r t i c l e i n f o
a b s t r a c t
Article history: Received 30 November 2016 Received in revised form 13 February 2017 Accepted 18 February 2017 Available online 21 February 2017
Primary sternal osteomyelitis (PSO) in the pediatric population is a rare infection with potentially catastrophic ramifications. We describe a case in a seven-month-old male patient who presented without evidence of trauma or a source of infection. Open sternal biopsies and cultures revealed Methicillin Sensitive Staphylococcus Aureus (MSSA) as the organism. We discuss the preoperative and surgical management of this patient as well as the antibiotic treatment strategy. © 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
Keywords: Primary Sternal Osteomyelitis Pediatric MSSA
1. Introduction Osteomyelitis often begins as seeding of bacteria from an external source introduced by trauma, contamination of foreign material, or hematogenous spread from a nidus of infection [1,2]. Primary osteomyelitis is a diagnosis made after exclusion of other sources of infection. Subsequent inflammatory changes result in vascular compression and ischemia of local bone tissue. Ischemia leads to necrosis and local inflammation produces a paradoxical activation of osteoclastic and aberrant osteoblastic activity. In children, hematogenous osteomyelitis is typically isolated to a single site with the majority occurring in tubular long bones [1,2]. In addition, primary osteomyelitis in the pediatric population is often associated with superficial wounds deemed to be clinically unimportant. Osteomyelitis involving the sternum and sternoclavicular joints is rare in the pediatric population. In the adult, sternal involvement is more commonly associated with chronic indwelling central venous catheters, intra-venous drug abusers, and cardiac surgery patients who undergo median sternotomy. In 2015, a review of the literature by Schweitzer et al. found 74 reported cases of
* Corresponding author. E-mail address:
[email protected] (A. Tran).
primary sternal osteomyelitis in the pediatric population [3]. Although a variety of organisms have been identified in case reports, staphylococcus aureus, group B streptococcus, coagulase negative staphylococcus and bacteria of the streptococci species are most commonly associated with the neonatal and infant population [4,5]. The critical aspect in the management of sternal osteomyelitis is early recognition, identification of the causal organism, and culture-driven intravenous antibiotic therapy. The severity and extent of bony infiltration will determine if the infection will require surgical intervention. In a review of 74 cases by Schweitzer et al., approximately one half of the series required surgical debridement and resection [3]. 2. Case description This is a case report of a seven-month-old Caucasian male who was initially seen by their primary care provider for a left upper sternal chest wall mass noticed 72 h prior by his foster parents. The patient was referred to our surgical offices for further investigation and management. The foster parent's denied any fevers, chills, nausea, or emesis. The child was irritable. The boy was healthy otherwise without a contributory past medical, surgical history, or family history. Physical examination revealed a palpable fixed mass at the
http://dx.doi.org/10.1016/j.epsc.2017.02.006 2213-5766/© 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
A. Tran et al. / Journal of Pediatric Surgery Case Reports 19 (2017) 38e40
upper sternum over the left sternoclavicular joint that was tender to examination. There were mild erythematous skin changes over the mass without obvious fluctuance. There were no skin lacerations, abrasions, or defects. He was afebrile, mildly hypertensive, but otherwise vital signs were within normal limits. Admission laboratory investigations included a C-reactive protein of 3.33 mg/ dL, white blood cell count of 19.8 thou/uL, lactate of 2.8 mg/dL, and blood cultures that were sterile. Ultrasound revealed a 2.5 cm by 1.6 cm by 0.6 cm mass extending into the sternoclavicular joint with heterogeneous characteristics. Magnetic resonance imaging described a lesion with a destructive process with a heterogeneous central fluid signal with enhancement of both the anterior and posterior aspects of the sternum (Figs. 1 and 2). There were no other abnormal findings of the chest. The patient was not given antibiotics at this time as we planned to take the child to the operating room for cultures of the lesion and biopsy. Our differential diagnoses included osteomyelitis with and without an abscess component; however a neoplastic process could not be ruled out without biopsy. On the morning of hospital day 2 the patient had a temperature of 38.1 C making infection more likely than a neoplastic process. Intra-operatively, a tunnelled central venous catheter was placed in the right internal jugular for postoperative intravenous antibiotic treatment. Aspiration of the mass with a large bore needle revealed no fluid. Incision and drainage was then performed. A small amount of seropurulent fluid was identified at the centermost portion of the mass without a large abscess component. Both fluid and tissue cultures were sent to pathology. Inflammatory changes were noted in the surrounding tissue. Bone and tissue biopsies were taken sharply. Using a curette, biopsies and debridement of the underlying bone cortex was performed at the upper sternum. The area was thoroughly washed out with sterile saline and closed leaving a Penrose drain to facilitate drainage. A central venous catheter was placed for post-operative intravenous antibiotic treatment. Postoperatively, the child was empirically treated with intravenous vancomycin (15 mg/kg) and later switched to intravenous clindamycin (10 mg/kg) on postoperative day one. Cultures revealed MSSA. The child was discharged on postoperative day two with a four-week course of intravenous cefazolin (450 mg every
Fig. 1. MRI demonstrating the lesion with enhancement surrounding a non-enhancing region within the soft tissue overlying of the superior segment of the sternum with destruction of the both the anterior and posterior cortex of the bone of this sevenmonth-old male.
39
Fig. 2. MRI demonstrating a lesion with destructive components into the superior segment of the sternum affecting both the anterior and posterior cortices of the bone of this seven-month-old-male.
8 h) followed by a two-week course of cephalexin. The child was followed by our surgical clinic and has remained afebrile and without sequelae. The Penrose drain and central venous catheter were removed accordingly. 3. Discussion and conclusions A comprehensive review by Schweitzer et al. describes 74 cases of primary sternal osteomyelitis in the pediatric population in both the pre- and post-antibiotic era (1860e2015) [3]. Interestingly, 13 cases were diagnosed in the pre antibiotic area and 60 cases were diagnosed in the post antibiotic era. This discrepancy is likely due to improved diagnostic methods over time. Of those reported cases in the pre-antibiotic era, the majority of cases resulted in death (67%) highlighting the lethality of the illness. Overall, in the post antibiotic era Staphylococcus Aureus was the most common causative organism (49%) followed by Kingella Kingae (11)%. Salmonella was isolated in 8% of cases, all of which occurred in sickle cell anemia patients. Patient Survival was achieved in approximately 95% of these cases with 75% requiring surgical treatment in addition to antibiotic therapy. The study identified 30 cases occurring over the past decade. The most common causative organism over the past decade has been Staphylococcus Aureus (56%) followed by Kingella Kingae (23%). Causative organisms failed to be reported in most cases from the pre antibiotic era. This article points out four cardinal features of primary sternal osteomyelitis: fever, erythema, tenderness, and swelling [3]. Our patient presented with swelling and tenderness with only erythematous changes and only later developed a fever. Only 11% of the cases reviewed by Schweitzer et al. possessed all four of these features. Presentation will be variable and will depend on the location of infection, the duration of infection, and the child's age. Symptoms are often non-specific and include irritability with a localized area of pain. Edematous and erythematous changes may be mild and progress in later stages of the infection. When there is a clinical suspicion, the patient should be referred for further investigation and management. Basic laboratory tests should include a white blood cell count, C-reactive protein, and erythrocyte sedimentation rate. A study by Unkilia-Kallio et al. found that WBC was only elevated in 36% of children with
40
A. Tran et al. / Journal of Pediatric Surgery Case Reports 19 (2017) 38e40
osteomyelitis, while ESR and CRP were elevated in 92% and 98%, respectively [6]. In the same study, ESR was found to take a period of three to five days to reach peak levels and upwards of four weeks to decline, while CRP increased more rapidly and also dissipated more quickly. Therefore, CRP is useful both in the early periods and for monitoring. Ideally, blood cultures, tissue cultures, and fluid cultures should be taken prior to administration of antibiotics. Antibiotic therapy should be culture-driven and should be delivered intravenously. The mainstay of treatment for primary osteomyelitis is culture driven antimicrobial therapy and early surgical debridement when appropriate. Treatment failure can occur if inappropriate antimicrobial therapy is chosen and surgical debridement is delayed. If inadequately treated, this condition can lead to local abscess formation with mediastinitis, chronic osteomyelitis with sinus tract or fistula formation, chest wall deformity, prolonged failure to thrive in children, and sepsis [1,3,4,7]. While diagnosis and treatment (including surgical treatment) for osteomyelitis is well recognized by orthopedic surgeons, it is rare for pediatric surgeons because the ribs and sternum are the only bones that fall within the prevue of that specialty. Nevertheless, a basic understanding is important, as the consequences may be significant for the child. PSO is a rare condition that can often present with subtle signs and symptoms in children. We present a case of a 7-month-old healthy infant who presented with a mass. We emphasize the need
for early diagnosis with surgical biopsy and culture especially in this age population. Ultimately the patient underwent prompt diagnosis with tissue cultures and treatment with intravenous antibiotics. Culture-driven therapy is essential. PSO in the pediatric population is a rare condition that should be on the differential for any patient presenting with localized swelling of the sternum, tenderness, and fever. The goal is early diagnosis and treatment to avoid later complications. References [1] Lew DP, Waldvogel FA. Osteomyelitis. Lancet 2004;364(9431):369e79. [2] Dartnell J, Ramachandran M, Katchburian M. Haematogenous acute and subacute paediatric osteomyelitis: a systematic review of the literature. J Bone Jt Surg Br 2012;94(5):584e95. [3] Schweitzer A, Della Beffa C, Akmatov MK, Narchi H, Abaev YK, Sherry DD, et al. Primary osteomyelitis of the sternum in the pediatric age group: report of a new case and comprehensive analysis of seventy-four cases. Pediatr Infect Dis J 2015;34(4):e92e101. [4] Narang A, Mukhopadhyay K, Kumar P, Bhakoo ON. Bone and joint infection in neonates. Indian J Pediatr 1998;65(3):461e4. [5] Wong M, Isaacs D, Howman-Giles R, Uren R. Clinical and diagnostic features of osteomyelitis occurring in the first three months of life. Pediatr Infect Dis J 1995;14(12):1047e53. [6] Unkila-Kallio L, Kallio MJ, Eskola J, Peltola H. Serum C-reactive protein, erythrocyte sedimentation rate, and white blood cell count in acute hematogenous osteomyelitis of children. Pediatrics 1994;93(1):59e62. [7] Lin JC, Miller SR, Gazzaniga AB. Primary sternal osteomyelitis. Ann Thorac Surg 1996;61(1):225e7.