Cross-reactivity among conifer pollens.

BACKGROUND: There are increasing reports of Cupressaceae pollinosis from various geographic areas. Cross-reactivity among a limited number of species within the Cupressaceae family has been suggested. Juniperus ashei (mountain cedar) is the leading cause of respiratory allergy in South Texas. OBJECTIVE: This study examines in vivo and in vitro cross-reactivity among 12 Cupressaceae species, one Taxodiaceae species, one Pinaceae species, and an angiosperm. METHODS: Cross-reactivity among pollen extracts of mountain cedar (MC) and the other 14 trees was investigated by: (1) prick skin testing of each tree pollen extract in ten patients with MC pollinosis. (2) Ouchterlony gel immunodiffusion employing rabbit antisera to MC. (3) IgE immunoblotting using high-titer MC pooled human sera, and immunoblot inhibition after pre-incubation with MC protein. (4) Monoclonal antibody immunoblotting using a murine monoclonal antibody with strong affinity for the gp40 major allergen of MC. RESULTS: Positive skin wheal-and-flare responses occurred to all 12 Cupressaceae and Japanese cedar (the Taxodiaceae), but not to the Pinaceae or the angiosperm. In Ouchterlony gels, lines of identity or partial identity formed between MC and all pollens except the Pinaceae and the angiosperm. Immunoblots demonstrated IgE binding to the 40 to 42 kD protein in each Cupressaceae, and to a parallel band in Japanese cedar at 43 to 46 kD. Immunoblot inhibition by MC pollen was complete for all trees. The monoclonal bound both the 40 to 42 kD protein in 11 of 12 Cupressaceae species and the 46 kD band in Japanese cedar, but bound no protein bands in the Pinaceae or the angiosperm. CONCLUSION: Pollen proteins of the 12 Cupressaceae (including MC) and the Taxodiaceae (Japanese cedar) are extensively cross-reactive. In particular, the MC major allergen, gp40, is cross-reactive with 40 to 42 kD proteins of the other Cupressaceae and with the Japanese cedar major allergen of 46 kD. Component-based immunotherapy may someday allow a standard treatment for both Juniper-allergic and C. japonica-allergic patients.

Underdiagnosis of asthma in young adults presenting for USAF basic training.

The underdiagnosis of asthma has not been well studied previously. The purpose of this study was to determine whether the diagnosis of asthma had been made previously in young adults who were subsequently shown to have asthma upon entering military service. Questionnaires were answered by all airmen basic referred to the Allergy-Immunology Clinic at Wilford Hall United States Air Force Medical Center over an 11-month period. There were 192 airmen basic referred to rule out asthma, primarily because of respiratory symptoms with exercise. These airmen were evaluated by history, physical examination, pulmonary function tests and, in 67%, by histamine or exercise challenge test also. In those diagnosed with asthma, the evaluating allergist then determined whether the diagnosis of asthma had been made previously considered or not considered. In airmen basic diagnosed by our clinic with asthma, the diagnosis had been made previously in 45%, considered in 25%, and not considered in 30%. Undiagnosed asthmatic airmen tended to have mild and primarily exercise-induced disease. We conclude that there is a high incidence of underdiagnosis of asthma in the population studied. Exercise-induced asthma accounted for most of the undiagnosed asthma.

Allergic fungal sinusitis.

Allergic fungal sinusitis (AFS) is a noninvasive disease first described as a distinctive clinical and histopathologic entity more than 10 years ago. The typical patient is immunocompetent, atopic, has chronic sinusitis refractory to medical therapy, and 100% of those we have diagnosed have nasal polyps. Because of the histopathologic similarity to mucoid impaction of the bronchi seen in allergic bronchopulmonary aspergillosis, Aspergillus species were initially suspected as the causative agent. Subsequent reports include a number of non-Aspergillus-related cases. Both we and others have found a 7% incidence of AFS among chronic sinusitis patients requiring surgery. Relapse after surgical debridement and aeration is common and often responds to systemic corticosteroids. The diagnosis of AFS should be considered in all atopic patients with nasal polyps and chronic sinusitis. The clinical and histopathologic features of this disorder are reviewed.

Mountain cedar pollinosis: can it occur in non-atopics?

In 1984 Ramirez postulated the existance of two subgroups of patients with Mountain Cedar (MC) pollinosis. One subgroup had a single positive skin test (SPST) to MC only, lacked other atopic diseases, and required prolonged MC exposure to develop the disease. The second subgroup had multiple positive skin tests (MPST) in addition to MC, had other atopic diseases, and developed clinical symptoms after a shorter period of MC exposure. To validate these findings, and to explore the clinical and immunologic differences between these two subgroups, 13 SPST and nine MPST patients underwent immunotherapy with MC pollen extract. Six SPST and ten non-allergic controls did not receive immunotherapy. MC specific IgE (sIgE), MC sIgG, and MC sIgG subclasses were measured by ELISA pre and intra season. Symptom Medication Score (SMS) were measured during the MC season. SPST patients had a significantly lower baseline sIgE than MPST patients, 2.1 IU/ml versus 22.3 IU/ml, p = 0.023, and were also older than MPST patients, 52.4 versus 32.2 years, p less than 0.001. Baseline MC sIgG and MC sIgG subclass antibody levels were similar in both patient groups. SMS were lower in treated SPST patients compared to treated MPST patients, p less than 0.01, but in vitro responses to immunotherapy were not significantly different between the two groups. MC sIgE, MC sIgG, MC sIgG1 and MC sIgG4 rose in both treated groups. MC sIgG1 (but not MC sIgG4) rose during the MC season in both non-immunotherapy groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Hypersensitivity pneumonitis caused by Cladosporium in an enclosed hot-tub area.

A 48-year-old woman had an 18-month history of malaise and chronic cough with intermittent episodes of fever, chills, and pneumonic infiltrates. Transbronchial biopsy findings were consistent with hypersensitivity pneumonitis. Cultures of fungus from a hot-tub room in her home were positive for Cladosporium species. Serum precipitins were weakly positive for Cladosporium cladosporioides. Removal of the patient from the home environment led to a resolution of symptoms within 1 week. Within 4 hours of re-exposure to the hot-tub room, symptoms and signs and changes in leukocyte count and spirometric values again occurred. Bronchial provocation with a commercial extract of C. cladosporioides led to a similar pattern 5 hours after the initial challenge. This case identifies a previously unreported etiologic agent and environmental site for hypersensitivity pneumonitis.