Malacoplakia of Gall Bladder: Case
report and review.
(MP) is a rare granulomatous disorder,
mostly involving urinary tract. Few cases are reported about malakoplakia in gallbladder
(GB). It morphologically mimics other lesions like xanthogranulomatous
cholecystitis as well as malignancy 1.
We report a case of gall bladder wall
thickness, clinically suspected to be carcinoma and then revealed as malakoplakia.
We will discuss the condition in the context of other causes of gall bladder
A 65 year-old nondiabetic
female patient, presented with a complaint of upper abdominal discomfort.
Abdominal examination showed palpable non-tender mass in the right
hypochondrium. Signs and symptoms of acute pancreatitis were negative.
liver function tests, renal function tests, Serum amylase and serum lipase were
within normal levels. Ultrasonography whole abdomen revealed multiple stones, contracted
gall bladder with wall thickening and excluded presence of pancreatic and
peripancreatic tissue edema.
Clinically Gall bladder carcinoma was suspected. Open cholecystectomy was performed
and gall bladder specimen was referred to histopathological examination (HPE).
Grossly, GB specimen was measured 10x6x4 cm with thickened wall. Dissection
showed greenish velvety mucosa with areas of ulceration. obliteration of the
cavity by diffuse nodules with yellowish discoloration and impacted three blackish
stones Figure 1.
HPE was done
after staining the paraffin blocks with hematoxylin and eosin. Sections
examined from gall bladder wall revealed subtotally denuded mucosal lining with
thickening of the wall. Ulcerated area and lamina propria showed sheets of
foamy macrophages with rounded, concentrically layered intracytoplasmic
inclusions (Michaelis-Gutmann bodies) Figure 2. Rokitansky-Aschoff sinus was
There was no evidence of granuloma, polyps, dysplasia or malignancy .
The characteristic Michaelis-Gutmann bodies were stained positively for
periodic acid-Schiff stain Figure 3.
The patient’s postoperative period was non-eventful. She was given
broad-spectrum antibiotics. She is symptom free and on regular follow up.
Greek Malako “soft” + Plako “plaque”) was
first described in 1902 by Michaelis and Gutmann as a rare chronic
granulomatous disorder most commonly affecting the urinary system1. However it was discovered also to
affect a wide range of tissues, extraurinary malakoplakia remains an occasional diagnosis2–4.
There are few reported cases of malakoplakia in the gall bladder, wherein, it
is usually presented as wall thickness as in our case or mass lesion and open
cholecystectomy is indicated due to diagnostic suspicion of carcinoma as in our
Malakoplakia specimens reveal a soft yellowish mass. On routine staining, microscopic
examination shows aggregates of histiocytes with fine eosinophilic granular
cytoplasm (von Hansemann cells) admixed with intracellular and extracellular
basophilic discrete inclusions with concentric laminations known as Michaelis-Gutmann
bodies in a background of mixed inflammatory cells infiltrating stroma. These
bodies also demonstrate positive results using periodic acid–Schiff stain. They
stain with von Kossa stain for calcium and Perls Prussian blue stain for iron1.
necessary to differentiate MP from its mimickers; Xanthogranulomatous cholecystitis
and malakoplakia that can present in a similar pattern. Both are thought to be
part of spectrum of chronic inflammatory pathology, with difference that
malakoplakia is more aggressive and shows the presence of both intracellular
and extracellular Michaelis–Gutmann bodies as in our case.
Gallbladder involvement in autoimmune pancreatitis
as a part of IgG4-associated systemic disease is also a common mimicker. In our
case, this was excluded by lack of characteristic laboratory investigations and
by the absence of characteristic histopathological findings of this disease.
Although more than a century has passed since Malakoplakia’s original
recognition, the exact pathogenesis has not been fully recognized.
Malakoplakia is thought to result from insufficient lysis of bacteria by
findings suggest that the defective phagolysosomal activity may be due to decreased
intracellular concentration of cGMP which results in deficient fusion of
lysosomes with phagosome6. Partially digested bacteria
accumulate in monocytes or macrophages and lead to the deposition of calcium
and iron on residual bacterial glycolipid, resulting in accumulation of
inclusion structures in cytoplasm of histiocytes, the Michaelis–Gutmann
bodies which are considered to be
pathognomic of malakoplakia3,7.
explanation suggested that the defect may exihibit the expression of a genetic
disorder or an improper immune response like that observed in alcohol abuse,
malnutrition, post organ transplant, immunosuppressive drugs such as steroids
or cytotoxic agents, malignancy and chronic diseases such as diabetes mellitus
and autoimmune disease2.
Malacoplakia has been described also in association with several microorganisms:
E. coliis usually seen in cases of urinary MP, Rhodococcus aequi in patients with AIDS infection and pulmonary MP and Herpes simplex
virus in young patients with cerebral MP. Other bacteria (i.e. Proteus, Mycobacterium, Shigella, Klebsiella,
Staphylococcus, Streptococcus, Pseudomonas), fungi (i.e. Paracoccidiodes) and
parasites have also been reported6.
Development of malakoplakia in chronic cholecystitis could be observed in the
background of xanthogranulomatous cholecystitis, which is thought to result from
unsuccessful phagocytosis of the bile material8.
In our case patient, was nondiabetic female, free of any of reported risk factors,
the matter which refers to the possibility of multifactorial pathogenesis of
Although malakoplakia is considered as a benign pathological process that
requires local excision, it has been observed that many of these cases have
aggressive course including high disease recurrence with fistulisation and poor
response to antibiotics9.
More specific therapy with antibiotics that concentrate
in macrophages such as quinolone and trimethoprim-sulfamethoxazole is
associated with a high cure rate10. Bethanechol, a choline agonist, has been recommended
in combination with antibiotics and surgery with the principle that Bethanechol
may correct the decreased cGMP levels that are believed to interfere with successful
phagolysosomal activity. Ascorbic acid has been used also to increase the cGMP
and cAMP levels in monocytes, which may offer an effective strategy for
therapy, though it is still under trial11.
Discontinuation of immunosuppressive drug therapy is usually needed to treat
Attempts of curative surgery would appear to be supported in all cases of gall
bladder MP and its mimickers; gall bladder carcinoma and xanthogranulomatous
cholecystitis due to the difficulty of distinguishing them radiologically.