Detection of Microorganisms in Granulomas That Have Been Formalin-Fixed: Review of the Literature Regarding Use of Molecular Methods

Abstract

Granuloma is an organized aggregate of immune cells that under the microscope appear as epithelioid macrophages. A granuloma can only be diagnosed when a pathologist observes this type of inflammation under the microscope. If a foreign body or a parasite is not observed inside the granuloma, stains for acid-fast bacilli and fungi are ordered since mycobacteria and fungi are frequently the cause of this type of inflammation. It is calculated that 12 to 36% of granulomas do not have a specific etiology and many have wondered if with new molecular methods we could reduce this number. This paper will summarize the frequently known causes of granulomas and will present the recent literature regarding the use of molecular techniques on tissue specimens and how these have helped in defining causative agents. We will also briefly describe new research regarding formation and function of granulomas and how this impacts our ability to find an etiologic agent.

Bacterial Etiology of Skin and Wound Infections along with Antibiogram Profiling in Reference to Emerging Antibiotic Resistance in Animals

“…In another study, Guarner and Brandt (2011) described that histopathological techniques are good for the diagnosis of systemic fungal infections. Guarner (2012) reported presence of microorganisms in formalin fixed granulomas by histopathology, his findings were different than the results recorded in the current study but yet literature is sparsely available exploring involvement of bacteria in abnormal skin outgrowth in pet and domestic animals.…”

Histopathological Spectrum of Granulomatous Skin Lesions: A Review

“…Few serological tests and ancillary techniques that can be used for diagnosis of infectious and noninfectious granulomatous skin diseases are summarized in Table 2. [59][60][61][62][63][64][65][66] conclusIon Granulomatous reaction patterns are frequently encountered in dermatopathology and results from several etiologies. An apt clinical history, meticulous histolopathological evaluation, and good clinicopathological correlation are of utmost importance in arriving at the final diagnosis.…”

Breast and Cervix Uteri: Rare Locations for Mycobacterium Tuberculosis Infections and Complications-Cases Report and Literature Review

“…The diagnosis of breast TB must follow the general principles: clinical and laboratory. The clinical presentation of breast TB is variable regarding symptoms/signs: swelling of the breast-48.1% [10]; painless hard lump-approximately 60% cases, or pain is revealed as the first complain of some patients [67,68] or up to 18.5% of cases [10]; rarely are recorded multiple lumps, with irregular borders, sometimes with skin fixation or areola fixation, or to the underlying muscle or even chest wall, clinical findings imposing differential to breast carcinoma [69], situation which is much more suggested by the presence of an isolated breast mass, sometimes skin fixated-"peau d'orange" sign, and without an associated sinus tract; ulceration of areola [117], or of the skin covering the mammary gland [118]; abscess, unique or multiples [85]; skin thickening and skin sinus/ fistula/multiple discharge sinuses [70], nipple retraction or inversion, nipple hyperpigmentation or focal discoloration-when the disease is long time duration [69], or distruction of nipple-areola region [19], breast shape and sizes are changed, axillary lymphadenopathy (axillary lymph nodes are found in one-third of cases with breast TB). Constitutional symptoms as fever, weight loss, night sweats or a failing of general health are infrequently encountered [71,72].…”

“…The granuloma diagnosisisamicroscopicdiagnosis.The microscopy of the cervical specimen after radical hysterectomy reveals an aggregate of immune cells, appearing as epithelioid macrophages, and if a foreign body or a parasite is not observed inside the granuloma, stains for acid-fast bacilli, and fungi are ordered as mycobacteria and fungi (such as Cryptococcus, Blastomyces, Coccidioides and Aspergillus can be seen on hematoxyline-eosine, preferentially in the area of necrosis rather than the surrounding viable area) are frequently the cause of this type of inflammation [31]. In cases with samples fixed in formalin the detection of the infectious agent is recommended to be done by molecular analysis, PCR for MbT in the Romanian case [91,118].…”