Leukemia cutis is an uncommon extramedullary manifestation of acute myeloid leukemia (AML) caused by infiltration of the skin by leukemic blasts. Its clinical morphology is highly variable and may mimic infectious, inflammatory, or other neoplastic dermatoses, making tissue diagnosis essential. We report a 49-year-old man who presented with fever, epistaxis, and multifocal nodular and ulcerated skin lesions involving the right wrist, chest, and scalp, as well as gingival hyperplasia. Skin biopsy was reported to confirm cutaneous myeloid sarcoma, consistent with leukemia cutis in the setting of AML. Histopathology demonstrated dense dermal infiltration by atypical myeloid cells with relative epidermal sparing. The patient was diagnosed with AML with cutaneous involvement and was started on systemic chemotherapy. This case emphasizes the importance of early biopsy of suspicious skin lesions in patients with known or suspected hematologic malignancy and highlights the adverse prognostic implications of leukemia cutis.

Immune thrombocytopenic purpura (ITP) is a rare autoimmune condition characterized by isolated thrombocytopenia in the absence of an identifiable secondary cause. While most cases respond to first-line therapy, relapsed or refractory forms, particularly in patients with coexisting autoimmune disorders, pose significant diagnostic and treatment challenges. Recent reports have identified rare instances of autoimmune cytopenias following severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA vaccination, raising concern for potential immune reactivation in predisposed individuals with prior immune dysregulation. We present the case of a 68-year-old male with a history of ITP and autoimmune hemolytic anemia who developed a severe relapse of thrombocytopenia, epistaxis, and suspected gastrointestinal hemorrhage shortly after coronavirus disease 2019 (COVID-19) vaccination. Despite initial treatment with corticosteroids, intravenous immunoglobulin, and platelet transfusions, the patient experienced a second relapse requiring escalation of care with additional immunosuppressive therapy and close hematologic follow-up. Ultimately, his condition improved with a multimodal approach and coordinated outpatient management. This case is clinically significant due to its temporal association with COVID-19 vaccination and the relapsing nature of ITP in the setting of systemic autoimmunity. It underscores the importance of early recognition, timely intervention, and vigilant monitoring in preventing life-threatening complications. The report adds to a growing body of literature highlighting the need for individualized care strategies and post-vaccine surveillance in patients at heightened risk of autoimmune reactivation.

A 32-year-old previously healthy man developed abnormal behavior two days after the onset of fever. He had experienced epistaxis during consecutive work days prior to the onset. While clinical findings suggested encephalitis, blood cultures yielded methicillin-resistant Staphylococcus aureus (MRSA). No obvious local infectious foci were identified in the skin or soft tissues; however, brain MRI revealed multiple embolic-like lesions. The MRSA strain produced markedly elevated toxic shock syndrome toxin-1 (TSST-1), suggesting a toxic shock syndrome-like state. Although initial empirical therapy did not cover MRSA, targeted anti-MRSA agents were started following its identification. Assuming an occult infectious focus, intravenous anti-MRSA therapy was continued for 6 weeks after blood cultures converted to negative. He was discharged on hospital day 54 without neurological sequelae. Community-associated MRSA can cause severe sepsis even in young individuals, and encephalopathy may be the initial presentation. Clinicians should consider MRSA sepsis in the differential diagnosis of patients presenting with encephalitis-like symptoms. In this case, the preceding epistaxis suggested that nasal colonization served as the portal of entry.

Hereditary hemorrhagic telangiectasia (HHT) is a multiple-organ disease. Herein, we report a case of rupture of an undiagnosed pulmonary arteriovenous malformation (PAVM) during pregnancy in which good outcomes for both mother and children were achieved with transcatheter embolization. The patient was a pregnant 32-year-old Pashtun woman, G4P3, with a history of cesarean section. She had undergone pregnancy checkups at our hospital for a dichorionic diamniotic twin pregnancy. In gestational week 20, the patient experienced loss of consciousness at home and was transported by ambulance to our hospital. Her Glasgow Coma Scale score was 9 (E2V2M5) and her blood pressure was 57/27 mmHg. Blood test results showed severe anemia; right atelectasis and mediastinal shift were shown on chest radiography. Contrast-enhanced chest computed tomography revealed right hemothorax and a single pulmonary arteriovenous malformation measuring 35 mm in the middle lobe of the right lung. The patient was diagnosed with hemothorax due to rupture of the right PAVM. Emergency transcatheter embolization was performed, disappearance of the arteriovenous malformation was confirmed, and hemostasis was achieved. Recurrent epistaxis and telangiectasias on the tongue, buccal mucosa, and nasal cavity were noted, and the patient was diagnosed with HHT. An abdominal cesarean section was performed due to the low-lying placenta and right hydronephrosis. Two male neonates were delivered: one weighed 1988 g and the other 2166 g. Both mother and infants progressed well. This case illustrates how unrecognized HHT can lead to catastrophic PAVM rupture during pregnancy and emphasizes the lifesaving value of early diagnosis and prompt endovascular intervention. In addition, it highlights the critical importance of pre‑pregnancy screening for HHT to prevent life‑threatening complications.

Domestic dogs are frequently exposed to tick-borne pathogens such as Babesia vogeli, Hepatozoon canis, Anaplasma platys and Ehrlichia canis, which can cause a wide range of clinical manifestations, although little is known about the epidemiological and clinicopathological profiles of mono- and co-infections. This study aimed to characterize infection patterns and identify clinical and epidemiological factors associated with mono-infections, and co-infections with two or more pathogens in naturally infected dogs. We analyzed 181 dogs from a hospital population with suspected hemoparasitic infections, assessed hematocrit and platelet counts, and used statistical models (Chi-square, Fisher's exact test, odds ratios, and multinomial logistic regression) to evaluate associations between infection types and clinical or epidemiological variables. This is the first comprehensive Brazilian study correlating infection type with clinical and epidemiological factors. Dogs with a history of tick infestation were 3.41 times more likely to be co-infected with two pathogens, and infections involving two (84.6%) or three or more pathogens (90.9%) were more frequent in dogs without the use of tick control medications. Male dogs and those presenting epistaxis, hyporexia or anorexia, dehydration, onychogryphosis, and ectoparasites were more likely to be co-infected with three or more pathogens. Thrombocytopenia was common in all groups, with dogs co-infected with three or more pathogens showing 16.3 times higher odds and dogs co-infected with two pathogens had increased odds of anemia (OR = 2.11). These results underscore the importance of tick control and comprehensive pathogen screening in endemic regions, especially in Brazil's semi-arid northeast, to enhance diagnosis, management, and prevention strategies.

The new issue of Rhinology reflects the wide range of topics covered by our field, spanning epistaxis, fungal sinusitis, and olfaction, as well as tissue biomarkers that characterize inflammatory processes. As always, the studies are insightful, methodologically sound, and offer new perspectives for the treatment of the diseases that occupy rhinologists. Continuous progress in our field promises considerable benefits for our patients.

Chronic Rhinosinusitis with Nasal Polyps (CRSwNP) is a persistent inflammatory disease that may be resistant to medical management and recurs with traditional surgery. We report a 28-year-old male with a history of CRSwNP with comorbid asthma, who was resistant to all medical management, including saline irrigation, intranasal corticosteroids (INCS), and multiple courses of antibiotics, and elected against surgical intervention. Nasal endoscopy and imaging studies demonstrated bilateral polyposis and opacification of the ostia of all sinuses (Meltzer score 5 and Lund-Mackay score of 18). Serum IgE level remained significantly high. The patient declined surgical intervention but consented to treatment with human umbilical cord MSC-Exo (hUCMSC-Exo) intramucosal and intrapolyp injections while continuing his standard regimen of saline irrigation and INCS. The treatment was well tolerated, with only reported mild and transient epistaxis. At follow-up after two months, the patient experienced a rapid decrease in SNOT-22 score (56-6). However, the symptomatic relief had abated, and the symptoms returned gradually but did not reach baseline (SNOT-22 increased to 41). Conversely, asthma control remained stable during this time, and the serum IgE level showed an overall negative trend. Given the single-patient, uncontrolled design with concurrent INCS and short follow-up, causality cannot be inferred. This case supports feasibility/tolerability and generates hypotheses for larger controlled studies of this cell-free approach.