Primary and secondary intralymphatic histiocytosis.
BACKGROUND
Intralymphatic histiocytosis (IH) is a rare condition often associated with systemic disease. A benign condition, clinical presentations can vary greatly and its cause is largely unknown. Histologically, there are macrophages within distended lymphatic vessels, although this can be an incidental finding or the primary abnormality.


OBJECTIVE
We present a series of 7 cases of IH with and without disease associations, and a review of the literature. We propose IH as either primary (without associated conditions) or secondary (associated with systemic disease).


METHODS
This was a retrospective collection of patients whose skin biopsy specimens revealed intralymphatic collections of histiocytes. We reviewed their clinical presentation, disease associations, and staining of slides with CD68 in all cases, D2-40 in 5 cases, and HLA-DR in 4 cases.


RESULTS
Clinical features were highly variable, and not all cases were associated with systemic disease. One case had admixed reactive angioendotheliomatosis. All 4 cases stained for HLA-DR showed strong expression by the intralymphatic macrophages.


CONCLUSIONS
Retrospective analysis and limited numbers are limitations.


CONCLUSIONS
IH is not always associated with systemic disease although macrophage activation nevertheless implies immune activation.
St John's Institute of Dermatology, St Thomas' Hospital, London, United Kingdom. Electronic address: farrahbakr@doctors.org.uk.
Farrah
F
Bakr
St John's Institute of Dermatology, St Thomas' Hospital, London, United Kingdom.
Naomi
N
Webber
St John's Institute of Dermatology, St Thomas' Hospital, London, United Kingdom.
Hiva
H
Fassihi
Department of Dermatology, Royal Free Hospital, London, United Kingdom.
Victoria
V
Swale
St John's Institute of Dermatology, St Thomas' Hospital, London, United Kingdom.
Fiona
F
Lewis
Cambridge University Hospitals NHS Foundation Trust, Cambridge, United Kingdom.
Ed
E
Rytina
Department of Dermatology, Addenbrooke's Hospital, Cambridge, United Kingdom.
Galia Tamar
GT
Ben-Zvi
Department of Dermatology, Addenbrooke's Hospital, Cambridge, United Kingdom.
Paul
P
Norris
Nuffield Department of Pathology, John Radcliffe Hospital, Oxford, United Kingdom.
Olivia
O
Espinosa
Nuffield Department of Pathology, John Radcliffe Hospital, Oxford, United Kingdom.
Sunanda
S
Dhar
Gloucestershire Hospitals NHS Foundation Trust, Gloucestershire Cellular Pathology Laboratory, Cheltenham General Hospital, Cheltenham, United Kingdom.
Paul
P
Craig
St John's Institute of Dermatology, St Thomas' Hospital, London, United Kingdom.
Alistair
A
Robson
D000328:Adult; D000368:Aged; D004108:Dilatation, Pathologic; D005260:Female; D006684:HLA-DR Antigens / Q000378:metabolism; D015614:Histiocytosis / Q000175:diagnosis / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D006801:Humans; D007150:Immunohistochemistry; D042601:Lymphatic Vessels / Q000473:pathology*; D008262:Macrophage Activation; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
D006684:HLA-DR Antigens
CD68; Crohn's disease; D2-40; HLA-DR; intralymphatic histiocytosis; intralymphatic macrophages; rheumatoid arthritis