Malakoplakia Research Articles

Successful treatment of intestinal malakoplakia in a French Bulldog.

Malakoplakia is a rare granulomatous inflammation that has mainly been reported in the urinary bladder of dogs. Only one case of canine colonic malakoplakia has been reported to date; however, successful treatment of this disease has not been reported. Here, we report a case of colonic malakoplakia in a 5-month-old spayed female French Bulldog. The dog was referred to a veterinarian because of chronic diarrhea and mucinous blood feces; empirical treatment did not improve its condition. Histologically, numerous macrophages containing periodic acid-Schiff-positive granules infiltrated the lamina propria of the large intestine. Furthermore, targetoid basophilic inclusion bodies (Michaelis-Gutmann bodies) were observed. Complete clinical remission was achieved after 8 months of enrofloxacin treatment and favorable progress after 2 months of medication.

Colonic Malakoplakia in Renal Transplant Patient: Case Report and Literature Review

Abstract Introduction/Objective Malakoplakia is a relatively rare inflammatory condition defined by histiocytic infiltration with pathognomonic intracytoplasmic inclusions known as Michaelis-Gutmann bodies. The lesion has been strongly associated with immunosuppressed states. Although the exact mechanism is unknown, an infectious component, such as impaired bactericidal activity in macrophages is highly implicated which leads to deposition of calcium and iron on residual bacterial glycolipid. Although commonly identified in the genitourinary tract, malakoplakia has been found in virtually all organ systems. Methods/Case Report We hereby present a 44-year-old male with a history of renal transplantation, presenting with a history of chronic diarrhea for one year. Colonoscopy was performed which identified diverticulosis in the sigmoid colon and a 5 mm sessile rectal polyp. Histopathological examination of the polyp biopsy demonstrated chronic active colitis, histiocyte aggregates and numerous intracellular, basophilic, concentric, laminated and targetoid calcified structures that were highlighted by Von Kossa and iron stains. These structures are known as Michaelis-Gutmann bodies which are pathognomonic of malakoplakia. A literature review of 45 cases was completed by utilizing the PubMed database. The cases reviewed included involvement of the allograft, host kidney, bladder, colon, prostate, thyroid, submandibular gland, lung, and testicles. Many of the patients were managed with either long term antibiotics, reduction of immunosuppression, or excision of the lesion with improvement in symptoms and/or renal function. Results (if a Case Study enter NA) NA Conclusion Our case highlights the importance of diagnosing this benign entity on histology examination to allow early treatment and improvement in symptoms.

A132 A CASE OF COLONIC MALAKOPLAKIA PRESENTING AS A LARGE CECAL MASS : NOT EVERY POLYP HAS TO LOOK LIKE A NAIL

Abstract Background Malakoplakia is a rare inflammatory condition, commonly affecting the genitourinary system of immunocompromised patients. Gastrointestinal malakoplakia has been reported in the literature, with previous endoscopic findings mimicking mass lesions. Purpose To describe a case of colonic malakoplakia after referral for endoscopic management of a large non-pedunculated colorectal polyp. Method Case report and review of the literature. Result(s) Case Report An 80-year-old male with chronic kidney disease and remote renal transplant on immunosuppressive therapy (mycophenolate mofetil, tacrolimus, prednisone) was referred for endoscopic resection for a large non-pedunculated colorectal polyp in the cecum. Original presenting symptoms included chronic diarrhea, iron deficiency anemia, and fecal immunochemical test (FIT) positivity. A repeat colonoscopy demonstrated a 40mm Paris 0-IIA plaque-like lesion in the cecum with optical features not in keeping with adenomatous or serrated histopathology. Biopsies were performed with histopathology demonstrating normal colonic mucosa with confluent sheets of histiocytes with concentrically layered cytoplasmic inclusions, in keeping with malakoplakia. Literature review Malakoplakia, Greek for “soft plaque”, is a rare inflammatory condition characterized by impaired dysfunction in macrophages leading to the accumulation of incompletely degraded bacteria in phagolysosomes. Histologically, this appears as concentrically layered cytoplasmic inclusions, comprising the pathognomonic Michaelis-Gutmann bodies. Many bacterial organisms have been implicated in the development of malakoplakia, with E. coli being the most common; specifically in immunocompromised patients, whether from immunosuppressive medications, immunodeficiency syndromes, or clinical conditions precluding effective immune function. Malakoplakia commonly presents as a mass-like lesion and has been found in all organs, most commonly in the genitourinary system. Diagnosis is made by biopsy and allows for appropriate treatment, which is most commonly a reduction in immunosuppressive therapy and antibiotic therapy. Image Conclusion(s) Malakoplakia is rare but should be considered when a lesion with atypical optical evaluation features is found in immunocompromised individuals or those with recurrent infections. Please acknowledge all funding agencies by checking the applicable boxes below None Disclosure of Interest None Declared

S2182 A Case of Colonic Malakoplakia

Introduction: Malakoplakia is a rare histiocytic inflammatory response that is usually found in the urinary tract. Gastrointestinal involvement is considered the second most common location affected and is a result of dysfunctional macrophages. Histopathology is characterized by granular histiocytes with Micahelis-Gutmann bodies. Although usually an incidental finding, Malakoplakia is associated with immunosuppressive therapy, colorectal carcinoma and infectious diseases. Case Description/Methods: A 54-year-old man with a pmhx of alcohol use disorder was referred to clinic for acute, asymptomatic liver enzyme abnormalities. Laboratory findings were significant for AST of 270 U/L, ALT of 63 U/L, ALP of 65 U/L, and total bilirubin of 0.3 mg/dL. Further workup showed positive hepatitis B surface antigen, reactive hepatitis B core antibody and hepatitis B DNA by PCR was 172K IU/mL. Patient underwent screening colonoscopy which revealed a 2 mm sessile polyp in the cecum (Figure A). Histological examination of the polyp showed von-Hansemann cells containing Michaelis-Gutmann bodies, which is diagnostic for malakoplakia (Figure B). Discussion: The first report of colonic malakoplakia was described by Terner and Lattes in 1965 and usually involves the ascending colon, sigmoid colon and rectum. Clinical manifestations of colonic involvement range from asymptomatic to abdominal pain, fever, diarrhea and rectal bleeding. The lesion is characterized by von-Hansemann cells which are aggregates of histiocytes with eosinophilic cytoplasm and intracytoplasmic Michaelis-Gutmann bodies. Pathogenic mechanisms include a causative organism, altered immune response and phagocyte disfunction. Escherichia coli is the most common isolated pathogen found in 90% of patients with malakoplakia. These chronic bacterial infections are due to suspected abnormal macrophage function resulting in the inability to break down bacteria. The most susceptible include immunosuppressed patients who are post-transplant or have an untreated systemic disease such as chronic hepatitis. Antibiotic therapy, immunotherapy modification and surgical resection are the mainstay of management. While most cases of malakoplakia are diagnosed as incidental findings on screening colonoscopy, there does exist an associate with colorectal adenocarcinoma. Given the potential for significant morbidity if left untreated, malakoplakia diagnosed on incidental screening should prompt a work up for systemic infections, immune compromising diseases and malignancy.Figure 1.: A: Two mm cecum polyp denoted by yellow arrows. Figure B: High-power view of Malakoplakia (60x). Macrophages containing basophilic targetoid structures, known as Michaelis-Gutmann bodies.

Prostatic malakoplakia: clinicopathological assessment of a multi-institutional series of 49 patients.

Prostatic malakoplakia (MP) is rare, with only case reports and small series (< five patients) available in the literature. In this study we analysed an international multi-institutional series of 49 patients with prostatic MP to more clearly define its clinicopathological features. The median age was 67 years and the median serum prostate-specific antigen (PSA) was 7.5 ng/ml. MP was clinically manifest in most cases (28 of 45 patients with data available, 62%). Of 43 patients with detailed clinical history available, 21 (49%) had concurrent or metachronous malignancies (including prostate cancer). Diabetes or insulin resistance was present in 11 patients (26%). Additionally, three patients had a history of solid organ transplantation and one had HIV. Of note, six of 34 patients (18%) without concurrent prostate cancer had an abnormal digital rectal examination and/or lesions on magnetic resonance imaging (MRI) with prostate imaging reporting and data system (PIRADS) scores 4-5. The initial diagnosis was made on core biopsies (25 of 49, 51%), transurethal resection specimens (12 of 49, 24%), radical prostatectomies (10 of 49, 20%), Holmium-laser enucleation (one of 49, 2%) and cystoprostatectomy (one of 49, 2%). Tissue involvement was more commonly diffuse or multifocal (40 of 49, 82%). Von Kossa and periodic acid-Schiff stains were positive in 35 of 38 (92%) and 26 of 27 lesions (96%), respectively. Of note, two cases were received in consultation by the authors with a preliminary diagnosis of mesenchymal tumour/tumour of the specialised prostatic stroma. The present study suggests that prostatic MP is often associated with clinical findings that may mimic those of prostate cancer in a subset of patients. Moreover, MP may be found incidentally in patients with concurrent prostate cancer.

S1858 A Case of Colonic Malakoplakia in an Immunocompromised Patient

S1858 A Case of Colonic Malakoplakia in an Immunocompromised Patient

Mimickers of Urothelial Carcinoma and the Approach to Differential Diagnosis.

A broad spectrum of lesions, including hyperplastic, metaplastic, inflammatory, infectious, and reactive, may mimic cancer all along the urinary tract. This narrative collects most of them from a clinical and pathologic perspective, offering urologists and general pathologists their most salient definitory features. Together with classical, well-known, entities such as urothelial papillomas (conventional (UP) and inverted (IUP)), nephrogenic adenoma (NA), polypoid cystitis (PC), fibroepithelial polyp (FP), prostatic-type polyp (PP), verumontanum cyst (VC), xanthogranulomatous inflammation (XI), reactive changes secondary to BCG instillations (BCGitis), schistosomiasis (SC), keratinizing desquamative squamous metaplasia (KSM), post-radiation changes (PRC), vaginal-type metaplasia (VM), endocervicosis (EC)/endometriosis (EM) (müllerianosis), malakoplakia (MK), florid von Brunn nest proliferation (VB), cystitis/ureteritis cystica (CC), and glandularis (CG), among others, still other cellular proliferations with concerning histological features and poorly understood etiopathogenesis like IgG4-related disease (IGG4), PEComa (PEC), and pseudosarcomatous myofibroblastic proliferations (post-operative spindle cell nodule (POS), inflammatory myofibroblastic tumor (IMT)), are reviewed. Some of these diagnoses are problematic for urologists, other for pathologists, and still others for both. Interestingly, the right identification of their definitory features will allow their correct diagnoses, thus, avoiding overtreatment. The literature selected for this review also focuses on the immunohistochemical and/or molecular data useful to delineate prognosis.

Gallbladder malakoplakia masquerading as malignant primary on 18F-FDG PET/CT.

Gallbladder malakoplakia masquerading as malignant primary on 18F-FDG PET/CT.

19. The many faces of colonic malakoplakia: A case series and review of the literature

Background: Malakoplakia is a rare inflammatory response to Gram-negative bacteria, involving intracellular deposition of iron and calcium. It is associated with immunosuppression, and occurs most often in the bladder. Although rare, the colon is the most common extra-genitourinary site. Aims and methods: To identify cases of colonic malakoplakia, the Royal Prince Alfred Hospital histopathology data base was searched from 2009. A literature review was performed using PubMed with the term ‘malakoplakia’. Formalin-fixed paraffin-embedded slides were stained with haematoxylin and eosin, PAS and von Kossa. Results and conclusions: A 10-year case file review identified four cases of colonic malakoplakia. Ages ranged from 50–79 with 2 males and 2 females. Clinical presentation and endoscopic appearances varied widely with an incidental polyp, mucosal changes mimicking inflammatory bowel disease, and a pelvic mass lesion with overlying normal mucosa seen. In all cases the biopsies revealed numerous histiocytes and chacteristic Michaelis-Gutmann bodies highlighted with PAS and von Kossa stains diagnostic of malakoplakia. A literature review identified 31 published case reports in adults and 10 in children of colonic malakoplakia. These cases highlight the protean manifestations of colonic malakoplakia. Consideration should be given to the diagnosis in histiocytic infiltrates in the large bowel to facilitate appropriate clinical management.

WITHDRAWN: Well surgical outcome of malakoplakia and xanthogranulomatous pyelonephritis which presented in the same patient: A case report and literature review

Abstract Xanthogranulomatous pyelonephritis (XGP) and malakoplakia (MKP) are chronic inflammatory condition of kidney characterized by infiltration of inflammatory cells. We describe the case of a 82 year-old female with a diagnosis of XGP under ureteroscopy with biopsy, who underwent radical nephrectomy and final pathology report was malakoplakia. Both diseases may combine but it's rare. With this case we hope to bring further evidence to support that these two diseases are not mutually exclusive but they can present on the same patient.

1666 A Rare Case of Colonic Malakoplakia in an Immunocompetent Man With Prior Chronic Hepatitis C Virus Infection

INTRODUCTION: Malakoplakia is a rare chronic granulomatous condition related to a defect in macrophage phagolysosomal response in which engulfed bacteria are not destroyed. The urinary bladder is the most common site for malakoplakia to present and the gastrointestinal tract is a distant secondly reported site. Malakoplakia is often associated with conditions that cause immunodeficiency. We report a rare case of colonic malakoplakia (CM) in an asymptomatic, immunocompetent man with history of successfully treated hepatitis C virus (HCV) infection. CASE DESCRIPTION/METHODS: A 70-year-old African American man with a past medical history of treated HCV due to prior intravenous drug use, was referred by his primary care provider for screening colonoscopy. He was asymptomatic and clinical history was negative for inflammatory or other infectious diseases. He denied use of immunosuppressant medications. HCV RNA was undetectable. HIV serology was negative. No remarkable findings on physical examination. During colonoscopy, a single 5 mm sessile polyp was noted in the transverse colon and was removed (Figure 1). Histopathological analysis of polyp identified targetoid calcospherites on Von Kossa calcium stain consistent with Michaels-Gutman bodies, diagnostic of malakoplakia (Figures 2 and 3). On repeat colonoscopy four months later, a single 14 mm sessile polyp was found in the proximal descending colon with histopathology consistent with tubular adenoma. No findings suggestive of malakoplakia was noted, however, exam may have been limited due to poor bowel prep. DISCUSSION: In summary, malakoplakia has been reported to involve the urinary tract in approximately 75% of cases while the gastrointestinal tract is involved less than 10% of reported cases. CM is often associated with neoplasms such as adenocarcinoma, adenoma, and lymphoma and other non-neoplastic conditions such as infections, sarcoidosis, diabetes mellitus, alcoholic liver disease, immunosuppressive therapy, or other conditions of immunodeficiency. Though not previously reported, HCV could have played a role in development of CM. HCV as been reported to be associated with the development of cutaneous malakoplakia; therefore, we cannot exclude association of other extrahepatic manifestations. In conclusion, CM is a rare chronic granulomatous condition that can be incidentally found in immunocompetent individuals, more studies warranted to evaluate any association with HCV.

Malacoplakia of the urinary bladder: a case report and review of literature

目的 探讨膀胱软斑病的诊治水平，提高对该病的认识。 方法 将1例膀胱软斑病患者的诊治过程进行报告，并结合文献进行复习。 结果 本组1例患者，男，82岁，以无痛性全程肉眼血尿为首发症状，超声及CT均提示膀胱内占位性病变，膀胱镜黏膜活检病理诊断为膀胱软斑病。 结论 膀胱软斑症的确诊依赖于病理组织学的检查，膀胱软斑症可采取保守治疗及膀胱肿物电切术。

Colonic Malakoplakia: An Unusual Finding in a Healthy and Asymptomatic Elderly Patient

Colonic Malakoplakia: An Unusual Finding in a Healthy and Asymptomatic Elderly Patient

Malakoplakie de la glande sous-mandibulaire chez un patient transplanté rénal

Malakoplakia (MP) is a rare granulomatous disease, usually occurring in immunocompromised patients, linked to Escherichia coli infection. The lesions are usually located in the genitourinary tract, but there is a great variability in the topography and the clinical presentation. A 70-year-old diabetic kidney transplant patient under immunosuppressive treatment presented with a voluminous submandibular chronic lesion, involving the skin, associated with a burgeoning lesion of the oral mucosa. Histological examination of biopsies concluded to MP and bacteriological samples were positive for E. coli. Antibiotic treatment allowed for the regression of the lesion before surgical removal. Histological examination of resected material confirmed the diagnosis of invasive MP of the submandibular gland. The diagnosis of MP relies on histological examination, showing the presence of von Hansemann's cells and Michaelis- Gutmann bodies. The treatment is based on active antibiotics targeted against intracellular bacteria, possibly associated with surgery. We report the first case of MP involving the submandibular gland.

Rectal Malakoplakia in a Healthy, Asymptomatic Female

Rectal Malakoplakia in a Healthy, Asymptomatic Female

Colonic malakoplakia in a cardiac transplant recipient

Malakoplakia is a rare inflammatory condition which is usually seen in the urogenital tract and less commonly in the gastrointestinal tract. Gastrointestinal malakoplakia may be associated with organ transplantation. There are previously only three reported cases of malakoplakia in cardiac transplant recipient. We report a case of colonic malakoplakia in a 38-year-old male who underwent cardiac transplantation for dilated cardiomyopathy 4 years previously and who had been on tacrolimus and mycophenolate. The patient presented with history of diarrhea associated with fecal incontinence for the past 6 months. Ileocolonoscopic examination was within normal limits. A rectal biopsy was done to exclude microscopic pathology. Microscopy revealed expansion of the lamina propria by histiocytes admixed with a few lymphocytes. The histiocytes showed granular eosinophilic cytoplasm with intracytoplasmic presence of Michaelis-Gutmann bodies, rounded basophilic laminated structures having central core with a targetoid appearance. These stained positively for Von kossa stain for calcium and were diagnostic for malakoplakia. Although rare, malakoplakia may be associated with chronic diarrhea even if there are no macroscopic lesions seen during colonoscopy. The patient's symptoms resolved with long-term ciprofloxacin therapy.

Malakoplakia of the Pancreas and Colon in an Immunocompetent Host

Introduction: Malakoplakia is an uncommon inflammatory condition usually associated with an underlying immunodeficiency, gram negative infection, or malignancy. Most cases are of genitourinary etiology. We describe a case of malakoplakia with simultaneous presentation in the pancreas and colon in an immunocompetent host. Case Report: A 69-year-old male presented to his primary care provider for evaluation of fatigue, 20-pound weight loss, and early satiety. Physical exam was significant for a cachectic appearing male, with a benign abdominal exam. Fecal occult blood test was positive. Laboratory investigation revealed a Hgb of 9.4 g/dL, transferrin saturation 8%, and a ferritin of 39.5 ng/mL. Other labs included a WBC count of 6.2 K/uL (with a normal differential), platelet count 263 K/uL, and INR of 1.74. LFTs were within reference range. HIV was negative. Due to his profound anemia, he was referred for colonoscopy which was significant for an 8-mm nodular submucosal collection of macrophages consistent with malakoplakia. Upper endoscopy was unremarkable. A computed tomography scan of his abdomen demonstrated a 5.8 x 5.2 cm pancreatic head mass. An endoscopic ultrasound confirmed this finding in the setting of an otherwise normal pancreatic parenchyma and pancreatic duct. Fine needle aspirate of the pancreatic head mass was significant for Michaelis-Gutmann bodies. Colon and pancreas specimens were negative for bacteria or malignancy. The patient is currently undergoing empiric antibiotic treatment and is doing well. Discussion: Malakoplakia is an uncommon form of chronic inflammation with usual involvement within the genitourinary tract. Other involved organ systems include the gastrointestinal tract, integumentary system, respiratory tract, central nervous system, HPA axis, and lymphatic system. The Michaelis-Gutmann body is pathgnomic, being described as a phagolysome encrusted with calcium and iron salts. The etiology of Michaelis-Gutmann bodies are thought to be an abnormal response to incompletely digested bacterial fragments and hence has been associated with chronic bacterial infections. Most cases of colonic malakoplakia are associated with colonic adenocarcinoma. Cases of malakoplakia of the pancreas are limited and are usually associated with pancreatic adenocarcinoma. Our case report is the first to our knowledge of a patient presenting with concomitant malakoplakia of the colon and pancreas outside the setting of an immunocompromised state or malignancy. This case highlights the fact that not all cases of iron deficiency anemia are “colon cancer until proven otherwise” and vigilance for zebras should always be present in the clinician’s mind.

Silent Colonic Malakoplakia in a Living-Donor Kidney Transplant Recipient Diagnosed during Annual Medical Examination

Malakoplakia is a characteristic inflammatory condition, which is usually seen in the urogenital tract, and less frequently in the gastrointestinal tract. We present a case of colonic malakoplakia in an immunocompromised patient. A 55-year-old female visited the outpatient clinic for routine cancer surveillance. Her past medical history was significant for kidney transplantation 11 years ago, and she had been taking immunosuppressants. A colonoscopy revealed several depressed flat lesions and elevated polyps, which were 0.3 to 0.4 cm in size and accompanied by whitish exudates. A biopsy revealed an infiltration of histiocytes with ample granular eosinophilic cytoplasm, with some lymphocytes and plasma cells. Many histiocytes had the characteristic morphology, described as Michaelis-Gutmann bodies: one or several round basophilic structures of approximately 1 to 10 µm in size with some being laminated, some appearing homogeneous, and others having a dense central core with a targetoid appearance. These Michaelis-Gutmann bodies were positively stained on von Kossa stain, and were diagnostic for malakoplakia.

Disseminated Gastrointestinal Malakoplakia in a Patient with Evolving AML

Disseminated Gastrointestinal Malakoplakia in a Patient with Evolving AML

Malakoplakia of the Gastrointestinal Tract: Prevalence and Clinicopathological Associations

Purpose: Malakoplakia (MP) is a rare granulomatous condition thought to result from the insufficient killing of bacteria by macrophages; it is of uncertain clinical significance and can occur at any tissue site. It may be focal or widespread, involving multiple organs. Gastrointestinal MP has been described in association with a variety of conditions such as ulcerative colitis, diverticulitis, adenomatous polyps, and carcinoma. It has been reported to cause rectal bleeding, diarrhea, abdominal pain and simulate polyps or masses. This study reports on the clinicopathologic associations in a series of 8 patients. Methods: This study was conducted at Caris Life Sciences, a specialized gastrointestinal laboratory receiving specimens from outpatient endoscopy centers across the US. Biopsies are interpreted by a group of gastrointestinal pathologists who have achieved a high level of diagnostic agreement by using uniform diagnostic criteria and terminology. We analyzed electronic data from the Caris database, which includes demographic, clinical, and endoscopic information for each patient, the site of origin and the histopathologic report for each biopsy. From a series of over 600,000 patients who underwent upper or lower endoscopies with mucosal biopsies between January 2009 till May 2010, we extracted data for all patients who had a histopathologic diagnosis of MP. Results: There were 8 patients with MP, 7 women and one man, aged 26 to 85 years. Two patients were from LA, and one each from NC, PR, FL, AZ, MD and CA. MP was detected exclusively at a single site in the colon in all cases. No patient had MP in the upper gastrointestinal tract or the small intestine, and none had evidence of diffuse disease. MP was detected in lesions submitted as polyps in all cases: 3 polyps were from the cecum, 3 from the rectum, and one each from sigmoid and ascending colon. Reasons for colonoscopy were: screening for colorectal cancer in 4 patients, bowl habits changes (2 patients), diarrhea (1 patient), and abdominal pain (1 patient). Von Kossa and iron stains showed the diagnostic Michaelis-Gutman bodies in all cases. No previous history of infection, immunosuppression, or other relevant condition was reported in any of the patients. Conclusion: This series confirms that MP is an extremely rare condition, with a prevalence of <0.8 in 100,000 patients with gastrointestinal mucosal biopsies. MP was restricted to the colon in all cases. Clinical presentations were varied: four patients were asymptomatic and the others had changes of bowel habits that may not necessarily be related to MP. All cases were detected in polypoid formations. No MP was identified in “classic” cold climate states/territories.