Pigmented Purpuric Dermatoses

Am J Clin Pathol. 2007 Aug;128(2):218-29. Abstract quote

The categorization of pigmented purpuric dermatosis (PPD) as a form of cutaneous lymphoid dyscrasia has been suggested. Phenotypic and molecular studies were done on 43 patients with PPD. The molecular studies used a capillary gel electrophoresis T-cell receptor beta multiplex polymerase chain reaction assay.

There were 2 principal categories: polyclonal PPD represented by 22 cases and monoclonal variants comprising 21 cases. Monoclonal cases had extensive skin lesions. An identical restricted T-cell repertoire independent of time and location was observed. Approximately 40% of the monoclonal cases had clinical and pathologic features of mycosis fungoides (MF). In the polyclonal variant, disease outside the lower extremities was uncommon; there were no patients with MF. Striking reductions in CD7 and CD62L were seen in both groups.

PPD is a form of cutaneous T-cell lymphoid dyscrasia, based on the frequency of monoclonality, the preservation of persistent T-cell clonotypes, and extent of pan-T-cell marker loss. Stratification of lesions of PPD according to the molecular profile may be of significant value prognostically and influence therapeutic intervention.

Epidemiology
Disease Associations
Pathogenesis
Laboratory/Radiologic/Other Diagnostic Testing
Gross Appearance and Clinical Variants
Histopathological Features and Variants
Special Stains/ Immunohistochemistry/ Electron Microscopy
Differential Diagnosis
Prognosis
Treatment
Commonly Used Terms
Internet Links

EPIDEMIOLOGY	CHARACTERIZATION
SYNONYMS	Progressive pigmented purpura
INCIDENCE	Common
AGE RANGE-MEDIAN	Younger adults

DISEASE ASSOCIATIONS	CHARACTERIZATION
Isolated reports following exposure	Dyes Thiamine treatment Carbromal Meporbamate Diuretics Ampicillin NSAIDs Acetominophen Herbal remedies

PATHOGENESIS	CHARACTERIZATION
GENERAL	Several mechanisms have been proposed but no single theory has explained all of the changes Delayed humoral immunity Delayed hypersensitivity Perforater vein incompetence
T-CELL LYMPHOID DYSCRASIA
Lichen aureus: clinicopathologic features, natural history, and relationship to mycosis fungoides. Fink-Puches R, Wolf P, Kerl H, Cerroni L. Department of Dermatology, Medical University of Graz, Graz, Austria.	Arch Dermatol. 2008 Sep;144(9):1169-73. Abstract quote BACKGROUND: A possible association between lichen aureus (LA) and mycosis fungoides (MF) has been suggested in the past. We evaluated the clinicopathologic features of LA and its relationship to MF. Data from 23 patients with a clinicopathologic diagnosis of LA were reviewed. OBSERVATIONS: Lesions were asymmetrically localized on 1 area of the body (mostly 1 extremity) and were characterized histologically by dense, bandlike lymphocytic infiltrates. A monoclonal T-cell population was detected in half of the cases. After a mean follow-up of 102.1 months, 14 patients had no sign of skin disease, 7 patients had unmodified skin lesions, and 2 other patients with unmodified skin lesions had died of unrelated conditions. Treatment modalities did not affect the outcome. There was no relationship between the presence or absence of monoclonality and patient status at follow-up assessments. Conclusion Patients with classic lesions of LA do not show progression to MF.
Pigmented purpuric dermatosis: classification by phenotypic and molecular profiles. Magro CM, Schaefer JT, Crowson AN, Li J, Morrison C. Department of Pathology and Laboratory Medicine, Weill Medical College of Cornell University New York Presbyterian Hospital-Cornell Campus, New York, NY 10021, USA.	Am J Clin Pathol. 2007 Aug;128(2):218-29. Abstract quote The categorization of pigmented purpuric dermatosis (PPD) as a form of cutaneous lymphoid dyscrasia has been suggested. Phenotypic and molecular studies were done on 43 patients with PPD. The molecular studies used a capillary gel electrophoresis T-cell receptor beta multiplex polymerase chain reaction assay. There were 2 principal categories: polyclonal PPD represented by 22 cases and monoclonal variants comprising 21 cases. Monoclonal cases had extensive skin lesions. An identical restricted T-cell repertoire independent of time and location was observed. Approximately 40% of the monoclonal cases had clinical and pathologic features of mycosis fungoides (MF). In the polyclonal variant, disease outside the lower extremities was uncommon; there were no patients with MF. Striking reductions in CD7 and CD62L were seen in both groups. PPD is a form of cutaneous T-cell lymphoid dyscrasia, based on the frequency of monoclonality, the preservation of persistent T-cell clonotypes, and extent of pan-T-cell marker loss. Stratification of lesions of PPD according to the molecular profile may be of significant value prognostically and influence therapeutic intervention.

HISTOLOGICAL TYPES	CHARACTERIZATION
Classic	Variable infiltrate of lymphocytes and macrophages in upper dermis with lymphocytic vasculitis in papillary dermis in active cases May have more lichenoid changes in lichen aureus Variable extravasation of red blood cells in papillary dermis with hemosiderin, sometimes in macrophages
GRANULOMATOUS
Granulomatous pigmented purpura: an unusual histological variant. Kerns MJ, Mallatt BD, Shamma HN. Department of Dermatology, Wright State University, Dayton, OH 45408, USA.	Am J Dermatopathol. 2009 Feb;31(1):77-80. Abstract quote Pigmented purpuric dermatoses (PPDs) tend to vary clinically, yet share a similar histology. Granulomas are only rarely seen, with 4 prior reported cases, designated granulomatous pigmented purpura. Historically, granulomatous pigmented purpura has been seen in Asians. In this article, we report the case of a 42-year-old, white female with granulomatous pigmented purpura, the fifth such reported case in the literature. Histopathological examination revealed a granulomatous dermatitis with eosinophils, extravasated erythrocytes, melanophages, and vascular proliferation. These findings were consistently reported on subsequent biopsy 6 months later. This case illustrates a rare histological finding in PPDs. Medications associated with PPD are reviewed and the patient's use of mesalamine and balsalazide for ulcerative colitis are deemed potential triggers, given their relative similarity to aspirin, a known trigger of PPD. Although other granulomatous processes must be excluded in such patients, one must consider the possibility of granulomatous pigmented purpura in the appropriate setting.

SPECIAL STAINS/ IMMUNOPEROXIDASE/ OTHER	CHARACTERIZATION
CD4+	Majority of lymphocytes

DIFFERENTIAL DIAGNOSIS	KEY DIFFERENTIATING FEATURES
Mycosis fungoides	Rarely, MF may clinically and histologically resemble this disease