title: Cutaneous borreliosis associated with T cell-predominant infiltrates: a diagnostic challenge.
abstract: BACKGROUND
  With the exception of erythema migrans, Borrelia infection of the skin manifests much more commonly with B cell-rich infiltrates. T cell-rich lesions have rarely been described.
  
  
  OBJECTIVE
  We report a series of 6 patients with cutaneous borreliosis presenting with T cell-predominant skin infiltrates.
  
  
  METHODS
  We studied the clinicopathologic and molecular features of 6 patients with T cell-rich skin infiltrates.
  
  
  RESULTS
  Half of the patients had erythematous patchy, partly annular lesions, and the other patients had features of acrodermatitis chronica atrophicans. Histopathology revealed a dense, band-like or diffuse dermal infiltrate. Apart from small, well differentiated lymphocytes, there were medium-sized lymphocytes with slight nuclear atypia and focal epidermotropism. An interstitial histiocytic component was found in 4 cases, including histiocytic pseudorosettes. Fibrosis was present in all cases but varied in severity and distribution. In 5 patients, borrelia DNA was detected in lesional tissue using polymerase chain reaction studies. No monoclonal rearrangement of T-cell receptor gamma genes was found.
  
  
  CONCLUSIONS
  This retrospective study was limited by the small number of patients.
  
  
  CONCLUSIONS
  In addition to unusual clinical presentation, cutaneous borreliosis can histopathologically manifest with a T cell-rich infiltrate mimicking cutaneous T-cell lymphoma. Awareness of this clinicopathologic constellation is important to prevent underrecognition of this rare and unusual presentation representing a Borrelia-associated T-cell pseudolymphoma.
authors.affiliation: Kempf und Pfaltz, Histologische Diagnostik, Zürich, Switzerland. Electronic address: werner.kempf@kempf-pfaltz.ch.
authors.forename: Werner
authors.initials: W
authors.lastname: Kempf
authors.affiliation: Kempf und Pfaltz, Histologische Diagnostik, Zürich, Switzerland; Department of Pathology, Faculty of Medicine in Pilsen, Charles University, Prague, Czech Republic.
authors.forename: Dmitry V
authors.initials: DV
authors.lastname: Kazakov
authors.affiliation: private practice, Biel, Switzerland.
authors.forename: Eugen
authors.initials: E
authors.lastname: Hübscher
authors.affiliation: Dermatopathology Viollier SA, Lausanne, Switzerland.
authors.forename: Oliver
authors.initials: O
authors.lastname: Gugerli
authors.affiliation: private practice, Koeniz, Switzerland.
authors.forename: Andreas W
authors.initials: AW
authors.lastname: Gerbig
authors.affiliation: Private practice, Baden, Switzerland.
authors.forename: Regula
authors.initials: R
authors.lastname: Schmid
authors.affiliation: Dermatopathologie Friedrichshafen, Friedrichshafen, Germany.
authors.forename: Gabriele
authors.initials: G
authors.lastname: Palmedo
authors.affiliation: Dermatopathologie Friedrichshafen, Friedrichshafen, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Kutzner
mesh_terms: D000169:Acrodermatitis / Q000209:etiology; D000328:Adult; D000368:Aged; D000818:Animals; D025065:Borrelia burgdorferi / Q000302:isolation & purification; D004269:DNA, Bacterial / Q000302:isolation & purification; D003937:Diagnosis, Differential; D004890:Erythema / Q000209:etiology; D005260:Female; D005355:Fibrosis; D006644:Histiocytes / Q000473:pathology; D006801:Humans; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000150:complications; D008193:Lyme Disease / Q000150:complications / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology / Q000635:transmission; D016410:Lymphoma, T-Cell, Cutaneous / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D019310:Pseudolymphoma / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D016692:Receptors, Antigen, T-Cell, gamma-delta / Q000235:genetics; D012189:Retrospective Studies; D012867:Skin / Q000276:immunology / Q000382:microbiology / Q000473:pathology*; D017192:Skin Diseases, Bacterial / Q000175:diagnosis* / Q000276:immunology / Q000473:pathology; D013601:T-Lymphocytes / Q000473:pathology*; D064927:Tick Bites / Q000150:complications / Q000382:microbiology / Q000473:pathology
chemical_list: D004269:DNA, Bacterial; D016692:Receptors, Antigen, T-Cell, gamma-delta
keywords: T cell; borreliosis; cutaneous T-cell lymphoma; interstitial granulomatous dermatitis