History and Epidemiology of Lanolin Allergy
In 1922, a report described a German patient who developed a “skin reaction” to a cream that contained 6% wool alcohols.[21] Seven years later, Ramirez and Eller documented the first patch-test-positive case of allergic contact dermatitis from lanolin.[22] A handful of case reports of lanolin allergy were published during the 1930s,[23–25] but it was not until the 1950s, when several studies verifying the prevalence of lanolin sensitivity in dermatologic patients were published, that lanolin allergy became widely recognized. (Key studies are summarized in Table 3 to Table 5 .) Sulzberger and colleagues documented lanolin allergy in 1.14% of 1,048 patients with suspected contact dermatitis in 1953 whereas Baer and colleagues reported a higher rate (4.4%) in 637 dermatologic patients who used hydrous wool fat in 1955.[26,27] In 1961 and 1962, Hjorth and Trolle-Lassen reported that 1.8% of 1,878 patients had positive patch-test reactions to Eucerin (not further defined) and that 1.6% of 1,664 patients reacted to wool alcohols (30% in petrolatum [pet]).[28] Bandmann and colleagues reported a prevalence of 3% in 1972, similar to Mortenson's findings in a separate study in 1979.[29,30]
In 1982, the North American Contact Dermatitis Group (NACDG) published a 13-year study on reactions to cosmetics. Of 8,093 patients who were patch-tested for suspected contact dermatitis, 487 (6%) were designated as having contact dermatitis from cosmetics. Results of tests with lanolin, lanolin alcohol, or lanolin oil were positive in 20 (4.1%) of the 487 patients who were determined to have contact dermatitis from cosmetics.[31] Another study showed that 66 of 616 patients with dermatitis were found to be sensitive to wool alcohols and/or Amerchol L-101 (AL-101).[32] More recently, a retrospective study of patch-test patients in the United Kingdom showed a higher positivity rate of 4.9%.[33,34] Wakelin and colleagues found the prevalence to be lower in a large population of Londoners. They reviewed the patch-test results of 24,449 patients tested with 30% wool alcohols and quoted a positivity rate of 1.7%.[35] In the NACDG summary for 2003 to 2004, 113 (2.2%) of 5,145 patients undergoing patch testing for suspected contact dermatitis reacted to lanolin alcohol 30% pet. Current relevance (definite, probable, or possible) was 28.6%. This percentage of lanolin-positive patients was unchanged from that reported for 2001 to 2002 and was not significantly different from values reported for 1998 to 2000 (2.4%), 1996 to 1998 (3.3%), or 1994 to 1996 (3.3%).[36]
To our knowledge, only one study has estimated the incidence (rather than the prevalence) of lanolin allergy in a general population (see Table 5 ). In 1975, Clark collected data from three European hospitals, estimated the patient population served by the hospitals, and then determined the number of new cases of lanolin alcohol sensitivity per year. The centers and the number of patients served in each were as follows: (1) Wycombe General Hospital (Buckinghamshire, UK), 225,000; Sahlgrenska Hospital (Gothenburg, Sweden), 350,000; and the University of Lund Department of Dermatology (Malmö, Sweden), 250,000. Within this aggregated population, 54.4 new cases of lanolin alcohol sensitivity were detected per year. Applying certain exaggeration factors to account for the use of lanolin alcohols in place of lanolin, the use of keratolytics with patch tests, and secondary versus primary lanolin sensitivity, Clark determined the annual incidence of lanolin allergy in the general population to be 1.46 to 8.75 cases per million.[18] Importantly, the relevance of these positive reactions was not discussed, and true incidence would best be determined by following known patch-test-negative patients over time.
Dermatitis. 2008;19(2):63-72. © 2008 American Contact Dermatitis Society
Cite this: Lanolin Allergy: History, Epidemiology, Responsible Allergens, and Management - Medscape - Apr 01, 2008.
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