Suppurative Inflammation With Microabscess and Pseudocyst Formation Is a Characteristic Histologic Manifestation of Cutaneous Infections With Rapid-Growing Mycobacterium Species

Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
American Journal of Clinical Pathology (Impact Factor: 2.51). 11/2008; 130(4):514-7. DOI: 10.1309/DPCLAWWQNTB74JNB
Source: PubMed


Mycobacterial infections of the skin classically cause a granulomatous tissue reaction. We have observed a suppurative pattern of inflammation associated with infections by rapid-growing Mycobacterium species in immunocompromised patients. We report 6 cases in skin and soft tissue with an unusual but consistent lack of a predominance of granulomatous inflammation. Of the 6 cases, 4 had predominantly (approximately 75%) suppurative inflammation, 1 case predominantly demonstrated (approximately 75%) a mix of acute and chronic inflammation, and 1 case showed an approximately equal contribution of suppurative and granulomatous inflammation. All 6 cases showed abscess formation and numerous acid-fast bacilli (AFB) on AFB stain and were confirmed by tissue culture. Of these 6 cases, 2 had microabscesses with central pseudocysts harboring microorganisms. Five patients were taking oral prednisone, and 1 had an uncharacterized immunodeficiency. These cases highlight the need for awareness of this unusual manifestation of infection with rapid-growing Mycobacterium species, particularly in immunocompromised patients.

28 Reads
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Case report A 63-year-old woman presented with multiple tender, nonulcerating, erythematous nodules on her right hand and forearm for 10 days (Figure 1A). She was suffering from Sjögren's syndrome for more than 1 year and had been treated continually with azathioprine and prednisolone. Under the tentative diagnosis of erythema nodosum, an incisional biopsy was performed on her right forearm. Histopathology showed septolobular panniculitis, heavy infiltrates of neutrophils and granulomatous inflammation (Figures 1B and 1C). Periodic acid-Schiff (PAS) and acid-fast stains were negative. She was then treated with prednisolone 20 mg per day for suspected autoimmune panniculitis. The patient returned to our clinic 2 months after initial presentation. Multiple erythematous to purpuric macules, papules, and punched out ulcers spread centripetally over the patient's four extremities in a symmetrical distribution (Figure 2A). Tender erythematous nodular eruptions without ulcerations similar to her previous skin lesions at initial presentation were found over both hands and forearms (Figure 2B). There were no associated systemic symptoms, such as fever, chilling and myalgia. She was treated with higher dose of prednisolone of up to 60 mg per day for suspected autoimmune vasculitis by the rheumatologist. However, more papulonodules, ulcers and pustules developed over her extremities as we tapered the dose of systemic steroid. Another skin biopsy of a fresh pustule from her right hand was taken and submitted for both histopathology and culture. Acid-fast positive bacilli were found (Figure 3). Figure 2 (A) Multiple crusted erythematous to purpuric macules and papules over extremities. (B) Several erythematous subcutaneous nod-ules similar to the lesions seen at initial presentation were noted over both hands and forearms. In addition, pustules and crusted lesions were seen during her second visit. A B C Figure 1 (A) Multiple tender, nonulcerating, swollen erythematous subcutaneous nodules on her right hand and forearm. (B,C) Heavy infiltrates of neutrophils and granulomatous inflammation in the subcutaneous tissue were seen. The inflammatory response was centered in the panniculus (H&E, 20×, 100×).
    Dermatologica Sinica 12/2010; 28(4). DOI:10.1016/S1027-8117(10)60040-7 · 0.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: A patient with Hansen's disease received corticosteroids for a type 1 leprosy reaction and subsequently developed a new cutaneous lesion at the original biopsy site from which Mycobacterium fortuitum was cultured. A review of the literature found only two other cases of coinfection with atypical mycobacteria and Mycobacterium leprae, although there are many reports of pulmonary tuberculosis in patients with leprosy. This case highlights the diagnostic difficulties encountered when a patient has two different mycobacterial infections of the skin. The published experience emphasizes that such coinfection is remarkably uncommon in leprosy, despite the frequent use of high doses of corticosteroids for leprosy reactions.
    Journal of the American Academy of Dermatology 03/2011; 64(3):593-6. DOI:10.1016/j.jaad.2009.10.004 · 4.45 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Non-tuberculous mycobacteria represent a heterogenous group of opportunistic pathogens which differ from Mycobacterium tuberculosis in their culture characteristics and sensitivities to various antimycobacterial agents. The incidence of cutaneous infection by these organisms has increased dramatically in the past several years due to widespread use of immunosuppressive therapies. Clinically, the features can be diverse with many patients having unusual presentations. The histological changes vary from a predominantly suppurative process to pure granulomatous inflammation, depending on the duration of the lesion sampled and the immunological status. Although the microscopic features are not species specific, a predominantly suppurative dermatitis with small pseudocystic spaces is often seen in cutaneous infections by a rapid growing non-tuberculous mycobacterial species. The granulomatous inflammation accompanying such cases is often, either poorly formed or absent. An awareness of this phenomenon should prompt the histopathologist to request pertinent histochemical stains and also guide the clinician towards appropriate ancillary microbiological investigations.
    Diagnostic Histopathology 04/2012; 18(4):185–188. DOI:10.1016/j.mpdhp.2012.01.002
Show more

Similar Publications

Preview (2 Sources)

28 Reads
Available from