Colonic Malakoplakia: A Rare Finding in a Healthy Male

Abstract

Malakoplakia is a rare chronic granulomatous disease that may affect many organs, including the lung, brain, adrenal glands, pancreas, bone, and the genitourinary tract. The gastrointestinal tract is the most common site of involvement outside of the urinary tract. Herein, we present a case of a 65-year-old male who presented with abdominal pain and unintentional weight loss. Physical examination findings were unremarkable, but colonoscopy revealed an isolated large, flat, soft, and pale lesion in the transverse colon. Histopathological examination of the lesion showed expansion of the lamina propria due to numerous lymphocytes, plasma cells, neutrophils, and polygonal cells. Von Kossa stain showed small intracytoplasmic basophilic granular inclusions, and these histiocyte cells showed numerous Michaelis-Gutmann bodies, findings considered as diagnostic features of colonic malakoplakia. This is a rare case of isolated malakoplakia of the transverse colon diagnosed on endoscopic specimens. The majority of reported cases have shown an association between systemic diseases and colorectal adenocarcinoma. In addition, most reported cases of colonic involvement have been in the rectum, sigmoid, and right colon.

Malakoplakia of the gastrointestinal tract: clinicopathologic analysis of 23 cases

“…Mass forming tumors mimicking malignancy have also been described [6][7][8]. Malakoplakia was initially described and most commonly found in the genitourinary tract but since its initial discovery in the early twentieth century, it has been reported in nearly every organ system, including the gastrointestinal [9][10][11][12][13][14][15], liver [16], central nervous system [17], renal [18], and pulmonary tract [19]. The gastrointestinal tract is the second most common organ system for malakoplakia involvement and it has been seen in association with colonic adenomas and adenocarcinomas [9,20,21].…”

Colonic malakoplakia in a dual stem cell and cardiac transplant recipient: A case report and literature review

“…Endoscopic assessment for suspected gastrointestinal involvement is useful, particularly in the presence of equivocal non‐invasive imaging results. Findings may include patchy or diffuse inflammation, as in our case, or polyps, 21 discrete yellow‐colored plaques, strictures, fistulae, 16 or even normal mucosa 8 . These findings yield wide differential diagnoses including neutropenic colitis, malignancy, inflammatory bowel disease, or miliary tuberculosis, 14,16 or even lead to the erroneous conclusion that the etiology may be medication related.…”

“…Findings may include patchy or diffuse inflammation, as in our case, or polyps, 21 discrete yellow‐colored plaques, strictures, fistulae, 16 or even normal mucosa 8 . These findings yield wide differential diagnoses including neutropenic colitis, malignancy, inflammatory bowel disease, or miliary tuberculosis, 14,16 or even lead to the erroneous conclusion that the etiology may be medication related. Therefore, tissue biopsy is necessary to confirm the diagnosis, and also exclude other more common causes of diarrhea in immunosuppressed individuals, such as cytomegalovirus colitis.…”

“…Bacteria may be isolated from the blood or diseased tissue 6,11 . While the pathophysiology of malakoplakia is usually related to immune dysregulation that occurs in the setting of immunosuppression, it has also been rarely reported in immunocompetent individuals 15,16 and those with brief exposure to immunosuppressive medications 17 . Malakoplakia has been most frequently described in renal transplant recipients 10,18,19 as opposed to other solid organ recipients.…”

“…Abdominal CT may demonstrate non‐specific inflammatory changes or masses relevant to the site of involvement, 13 but there may be no appreciable radiographic pathology 16 . Endoscopic assessment for suspected gastrointestinal involvement is useful, particularly in the presence of equivocal non‐invasive imaging results.…”