PMID- 9185904
OWN - NLM
STAT- MEDLINE
DCOM- 19970825
LR  - 20190905
IS  - 0193-1091 (Print)
IS  - 0193-1091 (Linking)
VI  - 19
IP  - 3
DP  - 1997 Jun
TI  - Mixed connective tissue disease. A clinical, histologic, and immunofluorescence 
      study of eight cases.
PG  - 206-13
AB  - A study of the cutaneous eruptions of eight patients with mixed connective tissue 
      disease (MCTD) was performed to better characterize its dermatopathology and to 
      explore a role for the membrane attack complex of complement C5b-9 in lesional 
      pathogenesis. Nine lesional skin biopsies were obtained from eight patients with 
      MCTD and analyzed by conventional light microscopy. Direct immunofluorescence 
      (IF) and indirect IF using a monoclonal antibody to C5b-9 were applied in six and 
      five cases respectively. The biopsied cutaneous eruptions were characterized 
      clinically as photo-distributed erythematosus annular and/or papulosquamous 
      lesions mimnicking subacute cutaneous lupus erythematosus (SCLE) in five of eight 
      patients as an ill-defined, telangiectatic, scaly patch on the face in one 
      patient, palpable purpura in one patient, and dorsal hand blisters resembling 
      porphyria cutanea tarda (PCT) in another. With the exception of the latter two 
      patients, the histology appeared similar, comprising a cell poor and/or lichenoid 
      interface dermatitis with suprabasilar exocytosis around necrotic keratinocytes 
      in the absence of deep periadnexal or perivascular extension or conspicuous 
      follicular plugging, a pattern similar to that of SCLE. However, the lesions 
      differed from SCLE by virtue of vasculopathic alterations comprising vascular 
      ectasia, hypovascularity, and/or luminal thrombosis confined to the superficial 
      vascular plexus and a sclerodermoid tissue reaction, the latter seen in two 
      cases. One biopsy showed a pustular leukocytoclastic vasculitis (LCV). In another 
      case, a biopsied hand blister demonstrated a PCT-like appearance histologically, 
      namely, pauci-inflammatory subepithelial blister formation with hyalinization of 
      dermal papillae capillaries accompanied by an LCV. There was nuclear keratinocyte 
      decoration with IgG and C5b-9 in all cases studied, accompanied by a positive 
      lupus band test in two cases and homogenous deposition of immunoreactants along 
      the dermoepidermal junction and within vessels in the PCT-like eruption. Granular 
      vascular decoration with immunoreactants including C5b-9 was seen in two LCV 
      cases and in two biopsies from rashes clinically mimicking SCLE. Although the 
      epidermal pathology of MCTD mimicks that of SCLE, a concomitant vasculopathy 
      paralleling that seen in skin lesions of dermatomyositis distinquishes the 
      dermatopathology of MCTD from that of SCLE. Corroborating the role of 
      microangiopathy in the pathogenesis of the skin lesions of MCTD was the 
      demonstration of C5b-9 in blood vessels. The deposition of C5b-9 in keratinocytes 
      may explain the pattern Of IgG decoration of keratinocytes; the formation of 
      plasmalemmal pores may permit binding of immunoglobulin to antigens in the 
      nucleus and/or cytosol. The C 5b-9 complex may be the effector mechanism of 
      epithelial and/or endothelial cell injury in MCTD or may serve to augment the 
      effects of antibody-dependent cellular cytotoxicity.
FAU - Magro, C M
AU  - Magro CM
AD  - Department of Pathology, Beth Israel Hospital, Harvard Medical School, Boston, 
      Massachusetts, USA.
FAU - Crowson, A N
AU  - Crowson AN
FAU - Regauer, S
AU  - Regauer S
LA  - eng
PT  - Journal Article
PL  - United States
TA  - Am J Dermatopathol
JT  - The American Journal of dermatopathology
JID - 7911005
RN  - 0 (Complement Membrane Attack Complex)
SB  - IM
MH  - Adult
MH  - Complement Membrane Attack Complex/*analysis
MH  - Female
MH  - Humans
MH  - Keratinocytes/pathology
MH  - Lupus Erythematosus, Cutaneous/pathology
MH  - Male
MH  - Mixed Connective Tissue Disease/*immunology/*pathology
MH  - Porphyria Cutanea Tarda/pathology
MH  - Skin/pathology
MH  - Telangiectasis/pathology
EDAT- 1997/06/01 00:00
MHDA- 1997/06/01 00:01
CRDT- 1997/06/01 00:00
PHST- 1997/06/01 00:00 [pubmed]
PHST- 1997/06/01 00:01 [medline]
PHST- 1997/06/01 00:00 [entrez]
AID - 10.1097/00000372-199706000-00002 [doi]
PST - ppublish
SO  - Am J Dermatopathol. 1997 Jun;19(3):206-13. doi: 10.1097/00000372-199706000-00002.