INVESTIGATIVE REPORT
1095 Advances in dermatology and venereology ActaDV Acta Dermato-Venereologica ActaDV
Pemphigus Vulgaris and Pemphigus Foliaceus : Differences in Epidemiology and Mortality
Khalaf KRIDIN 1 , Shira ZELBER-SAGI 2 and Reuven BERGMAN 1
1
Department of Dermatology , Rambam Health Care Campus and Rappaport Faculty of Medicine , Technion-Israel Institute of Technology , and 2 School of Public Health , Faculty of Social Welfare and Health Sciences , University of Haifa , Haifa , Israel
Little is known about differences in epidemiological features and prognosis between pemphigus vulgaris ( PV ) and pemphigus foliaceus ( PF ). The objective of this study was to compare PV and PF patients regarding ethnic variations and mortality rates . Mortality of PV and PF patients was compared with age- and sex-matched control subjects in the general population . The study cohort comprised 207 patients with PV and 30 with PF diagnosed during the period 2000 to 2015 . The incidence rate of PV among Jews was 3.6- fold high er than among Arabs ( p < 0.001 ), whereas no ethnic predisposition to PF was noted ( p = 0.379 ). The risk of death for patients with PV was almost 3-fold higher than in the general population ( standardized mortality ratio ( SMR ) 2.6 ). For patients with PF , the risk of mortality was not significantly increased relative to the general population ( SMR 1.4 ). There is a racial predisposition to PV , whereas PF is sporadic . Mortality among patients with PV is higher compared with PF and the general population .
Key words : pemphigus ; vulgaris ; foliaceus ; epidemiology ; mortality ; prognosis .
Accepted May 22 , 2017 ; Epub ahead of print May 24 , 2017 Acta Derm Venereol 2017 ; 97 : 1095 – 1099 .
Corr : Khalaf Kridin , Department of Dermatology , Rambam Health Care Campus , POB 9602 , Haifa 31096 , Israel . E-mail : dr _ kridin @ hotmail . com
Pemphigus is a rare , chronic , potentially life-threatening , autoimmune blistering disease of the skin and mucous membranes . It has 2 major subtypes : pemphigus vulgaris ( PV ) and pemphigus foliaceus ( PF ). The aetiopathogenesis of pemphigus is characterized by acantholysis and intraepidermal blister formation , resulting from IgG autoantibodies directed against desmoglein ( Dsg ) 3 ( PV ) and / or Dsg 1 ( PF ), 2 transmembrane desmosomal glycoproteins ( 1 , 2 ).
Pemphigus has an uneven geographical and ethnic distribution . We recently reported that the incidence rate of all variants of pemphigus in northern Israel was 3-fold higher among Jews than among Arabs ( the major ethnic populations in Israel ), with an overall annual incidence of 7.2 / million ( 3 ). The annual incidence of PV is variable , and ranges from 0.76 / million in Finland ( 4 ) to 16.1 / million in Jerusalem ( 5 ). In most populations PF is less common than PV , and the estimated annual incidence varies between 0.5 – 1.0 / million in Western Europe ( 6 ) to 6.7 / million in Tunisia ( 7 ). PF is rare and sporadic worldwide , and its ethnic predominance is yet to be demonstrated ( 8 ).
The mainstay treatments for pemphigus are systemic corticosteroids and immunosuppressive therapy . The prognosis for patients with pemphigus has improved greatly since the introduction of corticosteroid therapy ; nevertheless , pemphigus remains a potentially life-threatening disease ( 6 ), with a relatively high mortality rate after diagnosis , ranging from 5 % to 30 % during various lengths of follow-up ( 9 – 11 ). In 2 recent studies from the UK and Taiwan , the risk of death was calculated as 2-to- 3-fold higher than in the control or general population ( 12 , 13 ). We have demonstrated previously that overall mortality of patients with pemphigus is 2.4-times greater than for the general population ( 14 ).
The differences in the risk of overall mortality in patients with PV and PF relative to the general population have not yet been investigated . Moreover , the mortality of PF , as a distinct disease relative to the general population , has not been profiled .
The objectives of this study were to investigate and compare the 2 major subtypes of pemphigus regarding : ( i ) the incidence rate in 2 distinct ethnic populations ; and ( ii ) mortality rates compared with the general population , by tracking an immunopathologically validated large cohort of consecutive PV and PF patients over an extended period of time . The data obtained represent the first comparison between PV and PF patients regarding mortality rates relative to the general population .
MATERIALS AND METHODS Study population
The study comprised all Israeli patients in Haifa ( population : 875,000 ) and the northern ( population : 691,000 ) districts with a new diagnosis of PV or PF from the beginning of January 1990 to the end of December 2015 ( 2008 census ). The study cohort also included 16 patients diagnosed between 1985 and 1989 , and followed up intensely during the study period .
To assess the incidence of PV and PF for an extended duration , we conducted a retrospective cohort study from January 2000 to December 2015 . Incidence data are more reliable from 2000 due to the installation of a computerized system in our institute , which enables confirmation of every PV or PF case , and due to a better accessibility to the Israeli census . Rambam Health Care Campus is the tertiary referral centre providing dermatology services for the entire north-west region of Israel , and is the only hospital in the region that offers diagnostic laboratory immunopathology sample analysis . Thus , regional patients with suspected pemphigus are
This is an open access article under the CC BY-NC license . www . medicaljournals . se / acta Journal Compilation © 2017 Acta Dermato-Venereologica . doi : 10.2340 / 00015555-2706 Acta Derm Venereol 2017 ; 97 : 1095 – 1099