Abdominal Catastrophes, Peritoneal Eosinophilia, and Other Unusual Events in Peritoneal Dialysis

Abdominal Catastrophe

In patients undergoing PD, the term abdominal catastrophe refers to the signs and symptoms associated with either severe visceral inflammation or perforation. This disorder is also called secondary peritonitis , intrinsic peritonitis , or peritonitis due to bowel perforation . Peritonitis secondary to visceral injury is infrequent and is associated with a higher risk of transfer to in-center hemodialysis (HD) or death compared with primary PD-related peritonitis.

Enteric peritoneal contamination may occur as a result of localized inflammation, such as with cholecystitis, diverticulitis, appendicitis, incarcerated hernia, or severe inflammation and/or visceral perforation, as with ischemic colitis or nonocclusive mesenteric ischemia, gangrenous cholecystitis, or perforated gastric or duodenal ulcer. It has been suggested that patients undergoing PD present with abdominal catastrophes more frequently than those undergoing HD or in the general population. However, this data is based on small, single-center studies, and no definitive conclusions can be made in this regard. Rarely, erosion of the Tenckhoff catheter into the ileum or colon may be the primary event leading to visceral perforation; this often is limited to patients with a dormant, indwelling access not being used for PD.

Notwithstanding the early reports, patients with autosomal dominant polycystic kidney disease do not appear to be at a higher risk for either diverticular disease or enteric peritonitis. Furthermore, the relationship of the presence of colonic diverticula to the occurrence of enteric peritonitis or abdominal catastrophe remains unclear. It appears that a large number (≥ 10) or size (≥ 10 mm) of diverticuli or a nonsigmoid location may predispose patients to a higher incidence of enteric peritonitis. Yet, most patients with diverticular disease never develop enteric peritonitis or visceral perforation; thus, the presence of diverticulosis should not be considered as a contraindication to PD.

The initial clinical presentation of peritonitis associated with abdominal catastrophes is indistinguishable from PD-associated peritonitis from other causes. An occasional patient will present with abdominal pain with clear dialysate effluent or septic shock. The presence of fecal or biliary material in the effluent, although highly suggestive, is rarely observed. The peritoneal white blood cell (WBC) count is usually higher than with other causes of peritonitis; however, the data are not sufficiently clear to recommend a reliable cut-off value for the peritoneal cell count. Pneumoperitoneum can be present in patients undergoing PD (see later discussion) but does not help in diagnosing visceral perforation. Other imaging studies, such as computed tomography (CT), are often unrevealing as well.

Microbiologically, abdominal catastrophes are associated with a single gram-negative, anaerobic, or fungal organism on the culture; polymicrobial peritonitis is infrequent, and reported to be present in fewer than 20% of patients. Conversely, fewer than 10% of patients with polymicrobial peritonitis have an underlying surgical cause; thus, routine use of laparotomy in patients, with more than one organism on peritoneal fluid culture, is probably inappropriate. The concentration of amylase in the peritoneal effluent appears to be promising—levels that exceed 500 IU/L seem to be highly suggestive of visceral perforation.

Given this, the diagnosis of abdominal catastrophes in patients undergoing PD is often delayed, and this, in turn, leads to a greater probability of an adverse outcome. Thus, a high index of clinical suspicion is needed to diagnose episodes of peritonitis associated with abdominal catastrophes and should be considered in patients with enteric peritonitis who respond inadequately or incompletely to conventional therapy. Early evaluation by a surgeon is recommended in patients suspected of having an abdominal catastrophe. Large perforations, such as those associated with gastric or duodenal ulcers or ischemic colitis, are often fatal, but smaller, such as those associated with appendicitis or diverticulitis, can be treated with antibiotics alone without need for transfer to in-center HD.

Pneumoperitoneum

In the general population, the presence of air under the diaphragm is considered to be diagnostic of visceral perforation and a trigger for surgical intervention. This remains a potential cause for pneumoperitoneum in patients undergoing PD as well. However, the PD catheter provides an additional port of air entry into the peritoneal cavity; in some patients, the reason for air under the diaphragm on radiography may be related to PD. Pneumoperitoneum may occur after the placement of a PD catheter or manipulation or intervention involving the peritoneal access. Perhaps the most common PD-related cause of pneumoperitoneum is from incomplete priming of the tubing during the instillation of the dialysate that results in the infusion of air into the peritoneal cavity.

Inadvertent introduction of air into the peritoneal cavity may result in patients' presenting with sharp abdominal pain that radiates to the shoulder. However, most cases are diagnosed incidentally, and in an asymptomatic patient with an unremarkable abdominal examination, pneumoperitoneum is generally of little consequence. In a symptomatic patient with significant pneumoperitoneum, rapid relief has been reported with aspiration of air after draining the abdomen of all intraperitoneal dialysate and placing the person in the Trendelenburg position.

In the setting of peritonitis, the presence of pneumoperitoneum has a higher probability of being associated with underlying visceral perforation and requires radiologic workup and, if appropriate, exploratory laparotomy. Contrary to earlier reports, the size of pneumoperitoneum has little predictive value for the diagnosis of visceral perforation.