Abstract
While primary GAS peritonitis remains a rare cause of an acute abdomen in children, reports suggest a trend toward increased incidence.
Our report highlights a case of primary GAS peritonitis complicated by co-infection with C. difficile colitis, that required multiple drain placements and a prolonged antibiotic course.
The case suggests that forgoing extensive surgical washout of the abdominal cavity may contribute to adverse outcomes.
Case Report
A 14-year-old previously healthy female presented to another hospital with 5 days of nausea, emesis, diarrhea, and abdominal pain. Her most recent menstrual period was 10 days prior to presentation, and she denied sexual activity or retained tampon. Recent travel was limited to surrounding Midwestern states, and she denied exposures to animals and sick contacts. Initial laboratory testing revealed hyponatremia (131 mmol/L), hypokalemia (3.2 mmol/L), and hypoalbuminemia (2.7 g/dL) consistent with gastrointestinal losses, as well as leukocytosis (27.9 thous) with a significant bandemia (74% segmented neutrophils and 15% bands). Urinalysis demonstrated proteinuria (100 mg/dL) but was not suggestive of infection. Contrast-enhanced computed tomography (CT) abdomen showed acute diffuse gastroenterocolitis with moderate loculated ascites and small bilateral pleural effusions. Shortly following admission, the patient developed tachypnea and tachycardia. Due to the concern for sepsis in the setting of acute respiratory distress, she was transferred to the pediatric intensive care unit at our tertiary care center and broad-spectrum antibiotic therapy with piperacillin-tazobactam was initiated. Physical examination revealed an alert and fully oriented patient in mild distress with a temperature of 37.3°C, pulse of 153 beats/min, respiratory rate of 63 breaths/min and blood pressure of 118/90 mmHg. Breath sounds were diminished in the lower lobes bilaterally. Her abdomen was full and diffusely tender. Bowel sounds were not appreciated. The patient initially required high-flow oxygen therapy, but her respiratory status quickly improved. She was weaned to low-flow oxygen and transferred to the medical unit on hospital day #2.
Despite improvement in her respiratory status, she developed intermittent fever, peripheral edema, increasing abdominal distension, and persistent diarrhea. Repeat laboratory testing revealed worsening leukocytosis (36.3 thous), elevated acute phase reactants (C-reactive protein >27 mg/dL), and decreased complement levels (C3 69 mg/dL, C4 10 mg/dL). Blood cultures drawn on admission remained negative, but stool was positive for Clostridium difficile based on PCR testing. With this result, she was started on intravenous (IV) metronidazole and oral vancomycin therapy for severe C. difficile colitis on hospital day #3. Additionally, piperacillin-tazobactam was switched to ceftriaxone to maintain similar spectrum of coverage. An abdominal ultrasound obtained on day #4 confirmed moderate ascites and small bilateral pleural effusions; paracentesis yielded 120 mL of purulent ascitic fluid. Gram stain of the peritoneal fluid showed many segmented white blood cells and moderate gram-positive cocci with culture yielding Streptococcus pyogenes. She was transitioned from ceftriaxone to IV penicillin G therapy for treatment of primary group A streptococcal peritonitis.
Due to recurrent fever and persistent abdominal pain, a repeat CT was performed on day #11 and revealed a very large, loculated peritoneal fluid collection in the anterior abdomen and pelvis, measuring 38 × 6 × 22 cm (Figure 1A). One perihepatic drain and 1 left pelvic drain were placed by interventional radiology, removing 400 and 1600 mL, respectively. Cultures of the peritoneal fluid were negative. The perihepatic drain was removed after 3 days, while the left pelvic drain was removed after 6 days. IV metronidazole was discontinued on hospital day #12 following resolution of diarrhea. After 14 days of C. difficile colitis treatment, she was stepped down to once daily oral vancomycin as prophylaxis while on systemic antibiotics.
(A) Contrast-enhanced CT abdomen on day #11 showing large loculated fluid collection. (B) MRI abdomen without contrast at T2.Ax on day #19 with large right subphrenic and small left subphrenic abscess. (C) Final MRI abdomen without contrast at T2.Ax on day #61 showing near-complete abscess resolution.
Magnetic resonance imaging (MRI) abdomen with and without IV contrast obtained on day #19 secondary to continued abdominal fullness demonstrated significant reduction of the fluid collections in the anterior abdomen and pelvis with residual large right and small left subphrenic fluid collections (Figure 1B). Drains were again placed in the right upper quadrant, left upper quadrant, and perisplenic space, collecting 315 mL combined. The next day, the perisplenic drain was removed. She was discharged on hospital day #22 with cephalexin and prophylactic oral vancomycin. The remaining drains were removed in the following week. Two weeks after discharge, the patient had a follow-up MRI showing persistent though decreased fluid collections. She remained on cephalexin and oral vancomycin. Her final MRI obtained 1 month after discharge, revealed near-complete resolution of fluid collections (Figure 1C), and all antibiotics were discontinued after 61 days of total therapy.
Discussion
Bacterial peritonitis involves inflammation of the peritoneal lining of the abdominal cavity, and is usually defined as primary or secondary. Primary peritonitis refers to bacterial infection of the peritoneal cavity without a demonstrable intraabdominal source. Most cases occur in children with immune dysfunction or ascites resulting from cirrhosis and nephrotic syndrome. Secondary peritonitis, due to perforation of an intraabdominal viscus, occurs more frequently in the healthy pediatric population. The resulting peritonitis is predominately polymicrobial, while primary peritonitis is due to a single organism. 1
Streptococcus pneumoniae, gram-negative enteric bacilli, and Staphylococcal species are common pathogens implicated in primary peritonitis, while Streptococcus pyogenes is less prevalent. Group A Streptococcus (GAS) primarily causes upper respiratory tract and skin infections. Rarely, it causes gastrointestinal infection leading to an acute abdomen. 1 However, recent reports indicate a trend toward an increased incidence of primary GAS peritonitis. 2 The pathogenesis of primary GAS peritonitis remains unclear, although various theories have been proposed. Principal theories include hematogenous spread from the respiratory tract or skin, ascending infection in the female genital tract, and translocation from gastrointestinal tract and intact bowel.3,4 Review of pediatric literature reveals 13 reported cases of primary GAS peritonitis over the past decade. While several cases of primary GAS peritonitis have correlated with recent pharyngitis, our patient did not have these associated symptoms.5-8 Females are disproportionally affected, which suggests ascension from the female genital tract as a predominant source of infection. Case reports describe postpubertal females developing primary GAS peritonitis following sexual intercourse or gynecologic exam. 9 However, our patient denied sexual activity and has no history of gynecologic exam. Pharyngeal and vaginal cultures are often negative, thus a source of infection is not always identified.3,10
Children present with onset of acute abdominal pain, fever, vomiting, and diarrhea. Clinical presentation often mimics acute appendicitis, a more common cause of acute abdomen in children. Laboratory values may show leukocytosis and elevated acute phase reactants. Initial imaging may be normal or nonspecific, supporting the necessity of repeat imaging.7,8 Review of the pediatric literature reveals treatment consists of laparotomy to establish the diagnosis and treatment, with surgical exploration of the abdominal cavity and extensive washout.2-8,10-13 In contrast, our patient did not undergo exploratory laparotomy. However, she developed large loculated abscesses, requiring placement of multiple drains during her treatment course. Only 2 previous pediatric cases describe drain placement, both with insertion intraoperatively.3,6 In the literature, the duration of antibiotics ranges from 10 to 21 days (Table 1).2,3,10-14 Our patient required 61 days of antibiotic therapy, suggesting that laparotomy may decrease length of illness. Although penicillin G remains first-line for treatment and prevention of GAS infection, various antibiotics have been employed (Table 1).2-8,10-14 In this case, penicillin G was selected for inpatient treatment of peritonitis, while cephalexin was utilized as an oral alternative for outpatient antibiotic therapy due to ease of dosing.
Demographics and Clinical Presentation of Pediatric Patients With GAS Peritonitis From 1999 to 2019.
Peritoneal fluid obtained following initiation of antibiotic therapy; MRSA presumed to be secondary infection.
Conclusion
In summary, we describe a previously healthy 14-year-old female who presented with primary GAS peritonitis. Diagnosis was established via paracentesis rather than exploratory laparotomy. Multiple drain placements were required along with an extended antibiotic duration, highlighting the need for adequate source control. The course of illness was complicated by co-infection with C. difficile colitis, requiring treatment and prophylaxis for the total antibiotic duration.
Footnotes
Author Contributions
Conceptualization, formal analysis, interpretation, all authors; writing - original draft preparation, H.H.; writing - revision, all authors.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Ethical Approval and Informed Consent
Written informed consent for the publication of patient information in the case report was obtained from the patient’s guardians.
Funding
The author(s) received no financial support for the research, authorship, and/or publication of this article.
