Objective: We conducted an airborne pollen survey to determine the grass pollen dispersal period unaffected by other pollen dispersal and examine its regional characteristics.

Methods: The Airborne pollen count was investigated from May 1 to August 31, 2024, using the gravitational method, IS-type rotary pollen trap, at 13 cooperative pollen monitoring sites. The investigated pollens were Cupressaceae (except for Cryptomeria japonica), Alnus, Betula, Poaceae, Ambrosia, Artemisia, and Humulus japonicus. We set conditions for the start date, end date, peak start date, and peak end date of pollen dispersal and indicated the pollen dispersal period and peak dispersal period for each observation site.

Results: Grass pollen was collected from early June to mid-July at the pollen monitoring sites in Hokkaido, and at the other sites, from early May to mid-to-late August. Tree pollen is mainly collected from early May to early June. Grass-weed pollen other than grass pollen was mainly collected in mid-to-late August.

Conclusion: Based on this survey, the grass pollen dispersal period of low impact from other pollen dispersal was determined to be from June to July in Hokkaido and from May to August in other regions.

Background: The present study aimed to investigate the clinical characteristics and bronchodilator inhalation (BDI) responsiveness of asthma patients whose forced expiratory volume in one second to forced vital capacity ratio (FEV₁/FVC) remained below 70% after BDI.

Methods: This retrospective observational study included 130 patients diagnosed with asthma by respiratory specialists who had undergone airway reversibility test, and whose diagnoses could be confirmed from medical records.

Results: Among the 130 patients, 91 showed a post-BDI FEV₁/FVC ≥70% (N group), while 39 showed a post-BDI FEV₁/FVC <70% (O group). Peripheral blood eosinophil counts were significantly higher in the O group, whereas no other background factors differed between the groups. Before BDI, the percentage predicted FEV₁ (%FEV₁) and the percentage predicted forced vital capacity (%FVC) were significantly lower in the O group. After BDI, %FEV₁ remained lower in the O group, whereas %FVC did not differ significantly between the two groups. Both the absolute and relative increases in FEV₁ and FVC following BDI were greater in the O group. In the O group, the absolute increases in FEV₁ and FVC were comparable, whereas in the N group, the increase in FVC was smaller than that in FEV₁. The proportion of patients meeting criteria for airway reversibility (≥10% improvement in either FEV₁ or FVC from predicted values) was significantly higher in the O group.

Conclusion: Asthma patients with a post-BDI FEV₁/FVC <70% had more severe obstructive ventilatory impairment; however, their bronchodilator responsiveness was preserved, with a particularly marked improvement in FVC.

A man in his 30s with severe atopic dermatitis presented with recurrent bacterial skin infections over a one-month period, including lower leg cellulitis, persistent impetigo of the buttocks and extremities, and a carbuncle on the back. Despite incision and drainage, the carbuncle failed to improve, and he was referred to our department, requiring hospitalization. During hospitalization, he developed Kaposi varicelliform eruption. He had no known history of immunodeficiency; however, serologic evidence of prior syphilis infection was identified. Further evaluation revealed HIV antigen/antibody testing and an HIV RNA level of 74000copies/mL, leading to a diagnosis of HIV infection.

After discharge, his continuing episodes of recurrent carbuncles and furuncles induced him to initiate antiretroviral therapy. Following antiretroviral therapy initiation, his atopic dermatitis improved markedly. In the present case, it was considered that initiation of antiretroviral therapy might be associated with improvement in atopic dermatitis, suggesting that HIV treatment may modulate the activity of inflammatory skin disease.

As the cumulative number of individuals living with HIV continues to increase nationwide, recurrent skin and soft tissue infections should prompt consideration of HIV infection, even in non-urban regional settings. Early recognition and appropriate screening are essential for improving clinical outcomes.