Wednesday, 30 June 2021


Written by Fernando Calvo Boyero | Irene González Martínez | Alba Fernández del Pozo

Figure 1. Large organic structure with undigested plant appendages. Fragments of plant parenchyma (red arrow), isolated plant cells (green arrow) and yeasts with pseudohyphae (blue arrow) are observed on a background with a large number of bacteria. 20x optical microscope.

52-year-old man with no cardiovascular risk factors with a history of active alcoholic liver cirrhosis, Child B8, and portal hypertension who attended the emergency department due to deterioration in general condition, fever, abdominal pain in the right upper quadrant, and vomiting of less than 48 hours of evolution. A diagnostic paracentesis was performed with criteria of spontaneous bacterial peritonitis (410 leukocytes/uL, 70% polymorphonuclear cells) and a 1-liter evacuator, later entering the Digestive Medicine service.
During admission, the patient presented hepatic decompensation with ascites, for which a diagnostic and evacuating paracentesis was performed. An ultrasound-guided intramuscular short needle paracentesis is performed in the lower right flank, with no fluid leakage after two attempts. Subsequently, ultrasound-guided paracentesis was attempted in the lower left flank with a short intramuscular needle, with a dark brownish content that was sent to the laboratory.

In the biochemical analysis of the ascitic fluid, we found a glucose of 483 mg/dL, total proteins of 0.2 g/dL and LDH of 30 U / L. Cellular analysis did not identify red blood cells or leukocytes; however, we observed many microorganisms, with the presence of yeasts, muscle fibers, and plant cells (Figures 1 and 2). The absence of red blood cells and leukocytes, the microscopic findings, the fecaloid appearance, and the low protein concentration make the presence of gastrointestinal content in ascites fluid compatible.

The responsible physician is informed of the findings to treat the patient appropriately. In the imaging tests, no intestinal perforations, abscesses, or diverticulitis were observed, so the presence of fecal matter is probably the result of an intestinal microperforation originating during paracentesis. The patient is covered with linezolid and meropenem, and a sensitive Escherichia coli is subsequently cultured in the peritoneal fluid. In the following days, the patient is afebrile, with normal inflammatory markers, so antibiotic therapy is withdrawn and finally it is decided to discharge at home with outpatient control.

imagen2Figure 2. Remains of muscle fiber, where the yellowish color and striated texture stand out. 40x optical microscope.

The detection of yeasts in an ascitic fluid could make us think of a peritoneal candidiasis. However, the presence of other structures typical of the digestive tract (muscle fibers, plant appendages and other plant structures) in a serous fluid should make us suspect a contamination with digestive content, either by a fistula or an intestinal rupture. This pathology is known as fecaloid peritonitis, and it has a high mortality rate.

Therefore, microscopic analysis from the laboratory when detecting and interpreting these characteristic images, with many structures, can guide the diagnosis and help the initiation or intensification of antibiotic therapy, and thus improve the patient's prognosis, which can be fatal in fecaloid peritonitis.


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