Antigenicities of enteropathogenic Escherichia coli, lysozyme, and alpha-1-antichymotrypsin on macrophages of genitourinary malacoplakia

Malakoplakia as a cause of severe hypercalcemia through ectopic 25-hydroxyvitamin D3 1-alpha-hydroxylase expression: A case report

RATIONALE

Malakoplakia is a rare disease characterized by the presence of nongranulomatous macrophage infiltration. In most cases, it affects the urinary tract. Malakoplakia can cause acute kidney injury when it is localized in the kidneys.

PATIENT CONCERNS

Here, we report the case of a 65-year-old female patient with renal malakoplakia responsible for hypercalcemia. During her initial assessment, she was also diagnosed 25-OH vitamin D insufficiency, for which she was prescribed oral cholecalciferol. Three months later, she developed severe hypercalcemia with normal 25-OH vitamin D and parathyroid hormone levels and high 1,25-dihydroxyvitamin D levels.

DIAGNOSES

After a superimposed granulomatous disease was excluded, malakoplakia cells were suspected to be responsible for the abnormal 25-hydroxyvitamin D3 1-alpha-hydroxylase activity, which was confirmed by immunohistochemistry.

INTERVENTIONS

Cholecalciferol was stopped, the patient was rehydrated with intravenous physiological saline, and prednisone was initiated to decrease the enzyme activity.

OUTCOMES

Six months later, she displayed normal serum calcium, 25-OH vitamin D and 1,25-dihydroxyvitamin D levels.

LESSONS

This case illustrates that malakoplakia may exhibit ectopic 25-hydroxyvitamin D3 1-alpha-hydroxylase activity and cause severe hypercalcemia upon vitamin D supplementation. Therefore, such supplementation should not be given in malakoplakia patients without an actual deficiency and requires careful monitoring of serum calcium.

Digestive malacoplakia in children: case report

Malacoplakia is a form of chronic granulomatous inflammatory reaction that rarely affects the pediatric age group. The gastrointestinal system is the second most common site for the occurrence of malacoplakia. We report the case of a 9-year-old girl who was hospitalized for abdominal pain, chronic diarrhea, and rectal hemorrhage. The endoscopic examinations and histopathology confirmed the diagnosis of intestinal malacoplakia. We successfully treated her with oral levofloxacin. This disease does not have any specific clinical or biological signs, and the diagnosis is exclusively based on histology.

Focal malakoplakia in chronic periapical periodontitis

AIMS

Three cases of chronic periapical periodontitis including focal areas with malakoplakia changes are reported.

METHODS AND RESULTS

These areas included both von Hansemann-type macrophages and periodic acid-Schiff-positive, iron- and calcium-containing concretions. Some concretions corresponded to spherules with a targetoid configuration, thus fitting the morphological criteria for classical Michaelis-Gutmann bodies.

CONCLUSION

The vast majority of the cases of malakoplakia that have been reported in the literature corresponded to a characteristic, fairly homogeneous lesion, but a few instances of focal malakoplakia have been described in various chronic conditions. These considerations support the opinion that the local conditions for the production of Michaelis-Gutmann bodies may occur focally in diseases characterized by macrophage accumulation.