Malakoplakia - Causes, Clinical Features, Diagnosis, and Treatment.

Introduction

Malakoplakia is the term coined by Von Hansemann, which means soft plaque. Malakoplakia is an inflammatory condition occurring in immunosuppressed individuals affecting the urinary tract primarily and secondarily affecting the gastrointestinal, pulmonary, endocrine, lymphatic, musculoskeletal, integumentary, and central nervous systems. Malakoplakia of the urinary tract is more common in females, whereas cutaneous malakoplakia is common in males. The age group most affected is above 50 years of age.

What Are the Causes of Malakoplakia?

The causes of Malakoplakia include:

• Malakoplakia is found to be due to a bactericidal defect in the macrophages.

• The condition is associated with immunosuppression and is evident in individuals with organ transplants, malignancy, diabetes mellitus, human immunodeficiency virus (HIV), sarcoidosis, and connective tissue disorders.

• Malakoplakia is also found in association with X-linked agammaglobulinemia.

• Gram-negative bacteria cause Malakoplakia, most commonly Escherichia coli, but other microorganisms known to cause it are Klebsiella, Proteus, Corynebacterium, Pseudomonas, Staphylococcus, Streptococcus, Enterococcus, Mycobacterium, and Salmonella species.

What Are the Clinical Features of Malakoplakia?

• Malakoplakia commonly affects the perianal and genital areas with itchy, painful ulcerations, nodules, papules, and plaques. Individuals can present with hematuria, lower urinary tract symptoms, and recurrent urinary tract infections. It involves the other organs presenting as masses over the thorax, abdominal wall, head, neck, and extremities.

• The skin lesions are solitary or multiple arranged in lines and folds. They are usually skin-colored papules or nodules with a central draining sinus and tend to ulcerate.

• Malakoplakia can affect the tongue and give a feeling of a lump in the throat. However, a precise examination of the oral cavity reveals a soft, pink, or yellow-colored tumor mass on the base of the tongue. It is more common in males than females but is usually rare.

What Is the Pathophysiology Behind Malakoplakia?

The enzymes beta-glucuronidase and cyclic guanosine monophosphate are essential for regular phagolysosomal activity. But decreased levels of both enzymes are reported in malakoplakia. This shows that phagolysosomal activity is halted, and pathognomonic organisms are not yet eliminated. Thus reporting a defect in bactericidal activity.

How Is Malakoplakia Diagnosed?

Malakoplakia is diagnosed through the following methods:

• A complete history of the patient and a proper physical examination would provide clues for diagnosis.

• A skin biopsy is necessary to diagnose the cutaneous lesions and to rule out whether the lesion is neoplastic.

• The histological examination of tissue is characterized by sheets of von Hansemann cells with an inflammatory infiltrate of neutrophils, lymphocytes, and plasma cells. The von Hansemann cells are enlarged foamy cells with hyperchromatic nuclei and eosinophilic granules. The partially degraded pathogens present themselves in histology as Michaelis-Gutmann bodies, which are pathognomonic for this condition. They stain positive with von Kossa stain, periodic acid Schiff, and Perl's stain.

• The culture of the lesion is also done to plan the antibiotic treatment.

• Urinalysis indicates the presence of bacteria and white blood cells.

• In locally aggressive cases, malakoplakia can show bone erosions radiographically.

How Is Malakoplakia Treated?

• Malakoplakia is rare, and there are no specific treatment guidelines. However, the general management includes antibiotics, surgical excision, and the limitation of immunosuppression.

• Antibiotics such as Rifampin, Fluoroquinolones, and Trimethoprim can cause the killing of the cells by phagocytes. Successful antibiotic therapy takes a longer duration. The treatment can further be improved by adding anticholinergic agents and ascorbic acid, which help increase the cyclic guanosine monophosphate levels, thereby killing the bacteria.

• Catheterization of the individual under aseptic conditions would help. In addition, the bladder is rinsed with distilled water three times a day, and urinary symptoms are relieved using antiseptics like pyridium.

• If medical treatment fails, a surgical option is considered. The choice of surgery also depends on the site, size, and complexity of the lesion. For example, upper urinary tract Malakoplakia is found to be aggressive. If it affects the parenchyma of the kidney, a nephrectomy is performed. In addition, surgical excision or resection is advised if there is an obstruction in the ureter, urethra, and bladder. The most effective approach was the combination of medical and surgical treatment.

• Medications taken by immunosuppressed individuals can also cause malakoplakia. For example, individuals under prednisone and azathioprine, if they acquire malakoplakia, should stop the medicines for regression of the lesion.

How Is the Treatment Planned?

Malakoplakia is an inflammatory condition affecting nearly every body organ, and a professional team can best handle the disease. Such a team will have a primary physician, oncologist, dermatologist, infectious disease specialist, rheumatologist, and surgeon. Once the primary clinician identifies the condition, the dermatologist will perform a biopsy for histological examination. Then depending on the location and severity of the condition, the dermatologist, infectious disease specialist, and surgeon will formulate the treatment plan. Identifying the condition and treating it earlier will reduce the morbidity rate.

What Are the Differential Diagnosis for Malakoplakia?

The differential diagnosis for malakoplakia are,

• Actinomycosis.

• Botryomycosis.

• Tuberculosis.

• Lepromatous leprosy.

• Leishmaniasis.

• Sarcoidosis.

• Crohn’s disease (cutaneous).

• Lymphomas.

• Xanthomas.

• Foreign body granuloma.

• Transitional cell carcinoma.

• Squamous metaplasia of urothelium.

• Leukoplakia in bladder.

How Is the Prognosis of the Condition?

Malakoplakia associated with immunocompromised individuals usually regresses within four to six months duration. Cutaneous lesions are self-limiting conditions rarely resulting in death. An eighty percent curation rate is reported after surgery and antibiotic coverage. However, the disease can relapse rarely and can cause damage to the internal organs and local disfigurement despite surgical management.

What Are the Complications of Malakoplakia?

The complications of malakoplakia greatly depend upon the severity and location of the condition. For example, malakoplakia of the urinary tract can lead to infections, kidney injury, and renal failure.

Conclusion

Malakoplakia is a rare inflammatory condition, so a histological examination is crucial for a confirmatory diagnosis. Besides confirming the disease, they help in ruling out malignancy. The professional team will then plan the treatment based on the severity of the condition. Thus an individual with any symptoms should report to the physician immediately to get screened and treated at the earliest.