Streptococcus mitis Peritonitis in a Peritoneal Dialysis Patient: A Case Report Highlighting the Importance of Dental Hygiene

Viridans-group streptococci, including the Streptococcus mitis/oralis subgroup, can cause peritoneal dialysis (PD)-related peritonitis. The link between dental pathology and PD-related peritonitis remains to be fully elucidated. We report a case of an 83-year-old man undergoing nocturnal intermittent PD due to kidney failure from diabetic nephropathy who developed S. mitis peritonitis and septicemia traced back to a periodontal abscess. Despite having no prior history of peritonitis and maintaining good nutritional status, the patient presented with generalized abdominal pain and a low-grade fever. The initial treatment included intraperitoneal antibiotics. Root cause analysis identified multiple periodontitis and dental abscesses as the primary source of infection, confirmed by DNA sequencing of cultures from the abscesses and blood, which matched S. mitis. This case highlights the critical role of oral flora in causing invasive diseases in immunocompromised individuals, including PD patients, and illustrates how dental infections can lead to PD-related peritonitis through hematogenous spread. Our case also stresses the importance of meticulous dental care and regular dental examinations to prevent such infections in PD patients.

Peritoneal Dialysis-associated Peritonitis Due to Streptococcus oralis Three Weeks after Peritoneal Dialysis Initiation

A 60-year-old man with end-stage renal disease due to nephrosclerosis had a peritoneal dialysis catheter (PD) embedded with stepwise initiation of peritoneal dialysis using Moncrief and Popovich's technique three months ago. PD was initiated three weeks after creating an exit site. He presented with abdominal pain and fever a day before admission and was diagnosed with PD-associated peritonitis caused by Streptococcus oralis. Medical consultation after admission revealed a history of wisdom tooth extraction following PD catheter placement, resulting in delayed wound healing. Transient bacteremia can occur after tooth extraction, leading to PD-associated peritonitis. Contemplating the oral milieu in patients undergoing PD is pertinent.

Peritoneal Dialysis-Related Peritonitis Caused by Streptococcus oralis

A 77-year-old man developed peritoneal dialysis-related peritonitis caused by Streptococcus oralis, a rare pathogen causing the disease. The infection, which was not controlled by one-week intraperitoneal administration of cefazolin and ceftazidime, was cured only after switching to two-week intravenous administration of cefazolin and ceftazidime. The patient had no major dental disease or recent history of dental intervention. This case suggests that S. oralis might cause peritoneal dialysis-related peritonitis with persistent systemic inflammation via an extra-oral infection route. The clinical course is discussed along with a review of the literature.

Viridans streptococci in peritoneal dialysis peritonitis: clinical courses and long-term outcomes

BACKGROUND

The clinical courses and long-term outcomes of viridans streptococcus (VS) peritoneal dialysis (PD) peritonitis remain unclear.

METHODS

We conducted a retrospective analysis of all PD patients in a single center with gram-positive cocci (GPC) peritonitis between 2005 and 2011, and divided them into 3 groups: VS, other streptococci and other GPC (apart from VS). Clinical characteristics and outcomes of the VS group were compared with the other streptococci and other GPC groups, with prognostic factors determined.

RESULTS

A total of 140 patients with 168 episodes of GPC peritonitis (44% of all peritonitis) were identified over 7 years. Among these, 18 patients (13%) developed VS peritonitis, while 14 patients (10%) developed other streptococcal peritonitis. Patients with VS peritonitis had a high cure rate by antibiotic alone (94%), despite a high polymicrobial yield frequency (28%). We found that VS peritonitis carried a lower risk of Tenckhoff catheter removal and relapsing episodes than other GPC peritonitis (6% vs 11%), and a lower mortality than other streptococci peritonitis (0% vs 7%). However, after the index peritonitis episodes, VS, other streptococci, and other GPC group had a significantly increased peritonitis incidence compared with the period before the index peritonitis (all p < 0.01). Patients with VS peritonitis had a significantly higher incidence of refractory peritonitis compared with other streptococci or other GPC peritonitis in the long term (both p < 0.01).

CONCLUSIONS

VS poses a higher risk of subsequent refractory peritonitis after the index episode as compared with other streptococcal or GPC peritonitis. It might be prudent to monitor the technique of these patients with VS peritonitis closely to avoid further peritonitis episodes.

Streptococcal peritonitis in Australian peritoneal dialysis patients: predictors, treatment and outcomes in 287 cases

BACKGROUND

There has not been a comprehensive, multi-centre study of streptococcal peritonitis in patients on peritoneal dialysis (PD) to date.

METHODS

The predictors, treatment and clinical outcomes of streptococcal peritonitis were examined by binary logistic regression and multilevel, multivariate poisson regression in all Australian PD patients involving 66 centres between 2003 and 2006.

RESULTS

Two hundred and eighty-seven episodes of streptococcal peritonitis (4.6% of all peritonitis episodes) occurred in 256 individuals. Its occurrence was independently predicted by Aboriginal or Torres Strait Islander racial origin. Compared with other organisms, streptococcal peritonitis was associated with significantly lower risks of relapse (3% vs 15%), catheter removal (10% vs 23%) and permanent haemodialysis transfer (9% vs 18%), as well as a shorter duration of hospitalisation (5 vs 6 days). Overall, 249 (87%) patients were successfully treated with antibiotics without experiencing relapse, catheter removal or death. The majority of streptococcal peritonitis episodes were treated with either intraperitoneal vancomycin (most common) or first-generation cephalosporins for a median period of 13 days (interquartile range 8-18 days). Initial empiric antibiotic choice did not influence outcomes.

CONCLUSION

Streptococcal peritonitis is a not infrequent complication of PD, which is more common in indigenous patients. When treated with either first-generation cephalosporins or vancomycin for a period of 2 weeks, streptococcal peritonitis is associated with lower risks of relapse, catheter removal and permanent haemodialysis transfer than other forms of PD-associated peritonitis.