Pollen-food allergy syndrome (PFAS) is an oral allergy syndrome caused by inhalation of pollen antigens and commonly presents with local oral itching, numbness, and oral mucosal edema. These symptoms develop within several minutes of exposure to foods including fruits and vegetables; systemic symptoms such as anaphylactic shock are rare. We developed a novel PFAS murine model to analyze the underlying pathogenesis of PFAS. Birch-pollen-immunized mice were orally administered apple extract, and oral symptoms were evaluated based on oral rubbing frequency following the challenge. In the murine PFAS model, the oral rubbing frequency after the oral challenge with apple extract was significantly reduced in the birch-pollen-immunized Fcer1a^–/– mice and mast cell-deficient mice compared with the immunized wild-type mice. The apple extract stimulation did not increase the production of Th2-cytokine in the oral mucosa or the number of group 2 innate lymphoid cells or eosinophils. PFAS involves an early-phase response by mast cell degranulation via IgE signaling after the cross-reactivity of Bet v 1-specific IgE and the food allergen, and exacerbation of allergic symptoms via proteases in food; PFAS does not involve a late phase with local Th2/eosinophilic inflammation in the oral mucosa. This novel murine model might be utilized to elucidate the pathogenesis of PFAS and in the assessment of new therapeutic strategies for PFAS.

Background: Subcutaneous immunotherapy (SCIT) has been among the most effective treatments for allergic rhinitis for over a century. However, systemic reactions remain a serious problem with SCIT; they still occur in approximately 0.2% of injections. Recently, sublingual immunotherapy has been established as a safer treatment than SCIT. However, some patients require SCIT due to disease or compliance related issues. We investigated patients who underwent SCIT at our hospital and examined its safety.

Subjects: Patients who underwent SCIT using a mite and/or Japanese cedar pollen allergen extract in our department were investigated in this study.

Results: In total, 44 patients between 5 and 58 years of age underwent SCIT, and 9 (20.5%) experienced systemic reactions. Two patients treated using only mite allergen and seven using Japanese cedar pollen and mite allergens experienced systemic reactions. There was a significantly higher frequency of systemic reactions among patients in the dose-increase phase than in the maintenance phase (p<0.01). All patients who had systemic reactions exhibited whole skin eruption. All cases were properly treated, and no serious problems occurred.

Discussion: No statistically significant difference was observed in the risk of systemic reactions between SCIT using mite and Japanese cedar pollen allergens.

Several etiological factors contribute to deep neck abscess formation. We report a case of a deep neck abscess that occurred after transesophageal cardiac ultrasonography, together with a literature review. A 73-year-old man presented with a sore throat. The throat discomfort persisted, following transesophageal cardiac ultrasonography performed in late February 20XX, 3 days prior to his visit. The patient presented to our department for exacerbation of sore throat and onset of dyspnea. Physical examination showed evidence of poor dietary intake, neck erythema and edema, difficulty in neck extension, and a muffled voice. Laryngeal endoscopy revealed erythema and edema, the tendency to airway stenosis, and sputum and pus retention throughout the circumference of the laryngopharyngeal area. Computed tomography of the cervicothorax revealed a low-density area predominantly in the right visceral space with air on the right. Blood test results revealed significantly elevated inflammatory biomarkers. The patient was diagnosed with a deep neck abscess and airway stenosis. We performed emergency tracheostomy and abscess drainage. Postoperative fistulography and upper gastrointestinal endoscopy revealed no laryngopharyngeal and/or esophageal perforations. The patient was discharged on day 36 of hospital admission with a tendency towards reduction of the tracheal foramina. Patients with serious deep neck abscesses warrant prompt treatment after confirmation of the history. This patient developed significant complications, despite careful evaluation and monitoring after transesophageal cardiac ultrasonography. Patients who develop neck pain, dysphagia, fever, and/or dyspnea should seek prompt medical attention at an otolaryngology service.

We report a case of untreated pituitary adenoma complicated by bacterial meningitis that was diagnosed following nasal endoscopic surgery. A 68-year-old woman developed a headache and feeling of discomfort in the left ear. The patient was rushed to a nearby physician due to the lack of improvement. Head MRI showed inflammatory changes in the left papillary foci and sinuses, and the patient was transferred to our hospital with a provisional diagnosis of bacterial meningitis from sinusitis or otitis media. On arrival at the hospital, she exhibited a decreased state of consciousness, and acromegaly was suspected based on physical examination. Contrast-enhanced computed tomography showed a lesion with a contrast-enhancing effect from the left ethmoid sinus to the sphenoid sinus and bone defect in the skull base. It was necessary to differentiate between nasal intracranial complications, sinus tumors, and brain tumors and to drain any abscesses causing cerebral meningitis; thus, emergency nasal endoscopy and drainage were planned. While relieving the posterior ethmoid sinus, the partially whitened blood flowed out in a pulsatile manner, and an irregular pulsatile mass was confirmed and biopsied. The open wound was filled with the inferior turbinate mucosa in consideration of the possibility of cerebrospinal fluid leakage. Staphylococcus aureus was detected in the intraoperative wound culture. After pathological examination, with a diagnosis of pituitary adenoma was confirmed. Immediately after the surgery, the patient’s state of consciousness improved. In conclusion, this patient developed bacterial meningitis due to bony destruction of the ethmoid sinus canopy caused by an enlarged pituitary adenoma, and prompt drainage by nasal endoscopic surgery seems to have been useful.