Table 1.

Summary characteristics of case reports included in systematic literature search

Author	Year published	Country of publication	Age	Sex (M/F)	Description of appendicitis	Description of pericardial disease	Temporal relationship	Microbial analysis	Other parameters of infection/inflammation/SIRS	Pleural effusion present (Y/N)	Abdominal abscess present (Y/N)	Anesthetic management
Saha et al. [5]	2020	Canada	7	F	Acute suppurative appendicitis with perforation was diagnosed based on H & P, ultrasound, and later pathological analysis	Cardiac tamponade was diagnosed based on H & P, imaging, and EKG.	Symptoms related to appendicitis began 3 days before tamponade diagnosis. Appendicitis was diagnosed 3 days later.	The bloody sanguineous pericardial fluid tested negative for viral (CMV, EBV, HHV6, adenovirus), bacterial, and fungal infection. The serous pleural fluid was negative for bacterial culture. The blood, cerebrospinal fluid and urine also tested negative for viral, bacterial and fungal infection.	Elevated CRP; fever; tachycardia; tachypnea elevated WBC count (15.0 × 109/L)	Y (right side)	Y (two interconnected abdominal abscesses)	Pericardiocentesis was performed under conscious sedation (ketamine, midazolam, morphine, and local anesthesia) while maintaining spontaneous ventilation. Afterwards, laparoscopic appendectomy was performed under general anesthesia (propofol, midazolam, fentanyl, rocuronium, sevoflurane, and morphine)
Ku et al. [8]	2017	Australia	14	M	Perforated appendicitis was diagnosed based on H & P.	Pericardial effusion was diagnosed based on H & P and imaging	Pericardial effusion was diagnosed at least 8 days after the diagnosis of appendicitis.	Microscopic analysis of the hemoserous pericardial fluid revealed gram-negative rods, gram-positive cocci, and gram-positive rods. The culture of the effusion grew enteric gram-negative rods and mixed anaerobes including Streptococcus anginosus (S. milleri).	Fever; tachypnea; other parameters not reported	Y (bilateral)	Y (multiple abdominal abscesses)	Not reported
Tan et al. [9]	2004	Netherlands	12	F	Severe periappendicitis was diagnosed based on H & P and pathologic examination after appendectomy	Pneumo-hydropericardium, recurrent pericardial effusions and constrictive pericarditis was diagnosed based on H & P and imaging.	Symptoms related to appendicitis began approximately 12 days before pericardial effusion was diagnosed. Appendicitis was diagnosed 16 days later. Nine days later she developed pericarditis.	Blood cultures were positive for B. fragilis and S. milleri; Culture of the serosanguinolent pericardial fluid was positive for E. coli, S. viridans, C. albicans, but no anaerobes; abdominal cultures grew aerobic gram-negative rods, anaerobic gram-positive cocci, and enterococci	Elevated ESR (41 mm/h); fever; tachypnea; elevated WBC count (27.1 × 109/L); other parameters not reported	Y	Y (psoas abscess); lung abscess also present	Not reported
			13	F	Appendicitis was diagnosed based on H & P and during appendectomy, the appendix perforated. A fecalith was found in the appendix.	Purulent pericarditis was diagnosed based on H & P, imaging and EKG.	Appendicitis was diagnosed within 1–2 days of symptom presentation. Pericarditis was diagnosed after at least 17 days.	Pus evacuation occurred through the vagina and culture of the specimen grew E. coli, anaerobic rods (B. vulgatus), and peptostreptococcus species. Cultures of the pericardial fluid were negative.	Normal ESR (17 mm); fever; normal WBC count (11.5 × 109/L); Other parameters not reported	Not reported	Y (multiple intraabdominal abscesses including a Douglas abscess and subphrenic abscess)	Not reported
Kao et al. [7]	2002	Taiwan	3	F	Ruptured retrocecal appendix with an appendicolith was diagnosed based on H & P	Pericardial effusion diagnosed based on H & P	Symptoms related to appendicitis began at least 7 days prior to the diagnosis of a ruptured retrocecal appendix. Pericardial effusion was diagnosed at least 4 days later.	Culture of the abscess yielded group D beta-hemolytic streptococcus, E. coli, B. ovatus, and B. fragilis. The culture of the pleural fluid grew E. coli and B. ovatus. Urine, blood, and pericardial fluid cultures were all negative.	Fever; tachypnea; elevated WBC count (32,810/mm3) with left shift; other parameters not reported	Y (right side) and empyema	Y (right perinephric abscess)	Not reported
Speirs [11]	1951	Britain	11	M	Gangrenous appendix with pus in the peritoneal cavity was diagnosed based on H & P	Recurrent pericardial effusions with pericarditis diagnosed based on H & P and imaging.	Appendicitis was diagnosed within 2 days of symptom presentation. Recurrent pericarditis with pericardial effusion was diagnosed months later.	Culture of liver abscesses grew coliform organisms, non-hemolytic streptococci and S. albus. The pericardial fluid which was greenish-yellow and opalescent contained polymorphonuclear leukocytes and lymphocytes but was sterile when cultured	Fever; other parameters not reported	Y (right side)	Y (including liver abscesses)	Not reported
Mann [10]	1901	USA	12	F	Diagnosis of appendicitis was made based on H & P	Diagnosis of pericardial effusion and suppurative pericarditis was made based on H & P and gross examination	Appendicitis was diagnosed within 3–4 days after symptom presentation. Pericarditis with pericardial effusion was diagnosed 8–9 days later.	Septic shock; the bloody purulent pericardial fluid was positive for abundant pneumococcus	Fever; tachycardia; tachypnea; other parameters not reported	Not reported	Not reported	Ether was used for the pericardiocentesis; other information not reported

H & P history and physical, EKG electrocardiogram, CMV cytomegalovirus, EBV Epstein-Barr virus, HHV6 Human Herpesvirus 6, WBC white blood cell, ESR erythrocyte sedimentation rate, CRP C-reactive protein, SIRS systemic inflammatory response syndrome