Histologic Diagnosis of Inflammatory Skin Diseases

Identification of Basic Patterns: Skin: Nodular and Diffuse Dermatitis

…s processes, including lupus vulgaris, the recidivans form of leishmaniasis, and tuberculoid leprosy, the latter being the diagnosis here. Figure 5.180 A&B. A nodule formed by an abscess. A nodule constituted entirely of neutrophils is an absc…

Histologic Diagnosis of Inflammatory Skin Diseases

Cells That Mediate Inflammation (Inflammatory Cells)

…minance of either Th1 or Th2 cells. For example, in cutaneous leishmaniasis caused by infection with Leishmania tropica major, patients in whom a Th1 response predominates have strong cell-mediated immunity and are successful in destroying the parasi…

Histologic Diagnosis of Inflammatory Skin Diseases

Images

…is filled with tiny round monomorphous basophilic organisms = Leishmaniasis, acute An American, European, or Asian who bears such a lesion usually has returned from travel in the Middle East where a “bite” by a phlebotomus fly had been su…

Histologic Diagnosis of Inflammatory Skin Diseases

Leprosy

…ase. Differential diagnosis clinical Disseminated cutaneous leishmaniasis may be indistinguishable from lepromatous leprosy. Tinea versicolor can be distinguished from indeterminate leprosy by the presence of many more macules that are scaly and th…

Histologic Diagnosis of Inflammatory Skin Diseases

Applicable Terms

…being tuberculoid leprosy and the recidivans manifestation of leishmaniasis, and in noninfectious diseases such as rosacea and its variant, perioral/periocular dermatitis. Curiously, the granulomas of subcutaneous sarcoidosis tend to be tuberculoid i…

Differential Diagnosis in Dermatopathology

Discussions

…id leprosy includes lupus vulgaris and the recidivous form of leishmaniasis. Lupus vulgaris involves predominantly the upper part of the dermis by well-circumscribed aggregations of epithelioid histiocytes within which necrosis sometimes is noticeabl…

Differential Diagnosis in Dermatopathology

Tuberculoid leprosy vs. Sarcoidosis

An inflammatory process caused by Mycobacterium tuberculosis. In the skin, it may be primary as a consequence of direct inoculation (tuberculosis verrucosa cutis) or secondary to a focus of tuberculosis in another organ (the lung for lupus vulgaris,…

Histologic Diagnosis of Inflammatory Skin Diseases

Tuberculosis

…s nodular vasculitis.   Differential diagnosis clinical Leishmaniasis of the noduloulcerative type is indistinguishable morphologically from tuberculous chancre and from syphilitic chancre. Atypical mycobacteriosis and deep fungal infections ma…

Histologic Diagnosis of Inflammatory Skin Diseases

Syphilis

…nd a gumma by lupus vulgaris and the recidivans expression of leishmaniasis. Miscues clinical as clues to diagnosis histopathologic Denominators in common: Papules in annular configuration are noted. Features differentiating: Annular secondary s…