Search Results (322)

Background: CD8A-related CD8α deficiency (Immunodeficiency 116) is a rare autosomal recessive primary immunodeficiency disease characterized by absent CD8⁺ T cells and variable sinopulmonary disease. Case Presentation: A seven-year-old boy from a consanguineous family was referred for chronic wet cough and “uncontrolled asthma” despite being prescribed high-dose inhaled corticosteroids and montelukast. He was hospitalized seven times over a two-year period for presumed asthma exacerbations complicated by pneumonia. An examination revealed bilateral crackles without wheezing. Throat culture tested positive for Haemophilus influenzae. CT imaging showed signs of chronic rhinosinusitis (maxillary mucosal thickening) and chronic airway disease with bronchiectatic changes. The patient’s immunoglobulin levels were within normal ranges for his age group. Flow cytometry revealed profound CD8⁺ T-cell lymphopenia (CD8⁺ 0.21%; 11 cells/µL; near-absent after excluding dual-positive cells) with expansion of CD3⁺CD4⁻CD8⁻ T cells (29.5%). CD8A gene sequencing identified a novel homozygous nonsense variant NM_001768.7:c.319C>T (p.Arg107Ter; GRCh38: chr2:86790412G>A), consistent with loss of CD8α and secondary loss of CD8β surface expression. A literature review identified three previously reported symptomatic patients (and two asymptomatic sisters in the first family), all with recurrent respiratory infections and variable structural lung disease. Conclusions: This case highlights CD8A deficiency as a rare mimic of pediatric asthma and expands the genotype spectrum with a truncating CD8A variant. Early lymphocyte immunophenotyping in children with recurrent sinopulmonary infections may prevent delayed diagnosis and progressive airway damage. Full article

A 10-year-old castrated male Chihuahua weighing 3.06 kg was presented with a chronic, progressively worsening cough of five months’ duration. Diagnostic imaging, including thoracic radiography and computed tomography, identified a well-defined cranial mediastinal mass consistent with a thymic tumor. Surgical excision was performed via median sternotomy with complete thymectomy. Following tumor removal, sternal closure was achieved using a non-absorbable ultra-high-molecular-weight polyethylene (UHMWPE) suture material (FiberWire^®, Arthrex, Naples, FL, USA). Histopathological examination confirmed the diagnosis of an epithelial-predominant thymoma with narrow but complete surgical margins. Postoperative recovery was uneventful, and the dog was discharged three days after surgery. Clinical signs, including coughing, progressively improved during follow-up. Radiographic evaluation performed up to postoperative day 57 demonstrated stable sternal alignment without evidence of dehiscence, implant-related complications, or disease recurrence. This report describes the first clinical case of FiberWire use for median sternotomy closure following thymectomy in a dog. The favorable clinical and radiographic outcomes observed during postoperative follow-up suggest that FiberWire may represent a viable alternative to traditional stainless-steel wire for sternal fixation in canine thoracic surgery. Full article

Objective: To investigate the epidemiology, clinical characteristics, and potential risk factors of chronic cough following SARS-CoV-2 infection. Methods: A total of 1434 patients with post-COVID-19 cough were categorized into acute, subacute, and chronic subgroups by cough duration, with clinical data analyzed across subgroups. Questionnaire surveys were conducted in chronic cough patients, followed by an 18–21-month follow-up. Results: 1. Significant intergroup differences were observed among the three groups in: the number of patients with rhinitis and/or pharyngitis history, cough with chest tightness, cough with pharyngeal symptoms, and sensitivity to irritating odors and cold air. 2. The chronic group had a significantly lower platelet count but higher eosinophil and basophil percentages than the acute group. 3. The chronic group showed significantly lower values than the subacute group in multiple pulmonary function indices: FVC, FEV1, FEV1/FVC, PEF, MEF25, MEF75, MEF50, MMEF75/25, MEF75%, MEF50%, MEF25%, MMEF75/25%, DLCO, and DLCO%. 4. Chest CT findings: the chronic group had significantly lower rates of infected lesions, cord-like opacities, and ground-glass shadows than the acute group, but a higher rate of micro-nodules than the subacute group. 5. At follow-up, the cough and non-cough groups differed significantly in nighttime cough scores and the proportion of cough with chest tightness, as well as in pulmonary function parameters: FVC, FEV1, PEF, PEF%, MEF75, DLCO, RV% and TLC. 6. Binary logistic regression analysis identified the nocturnal cough symptom score and cough accompanied by chest tightness as independent factors influencing persistent cough 18–21 months after SARS-CoV-2 infection. Conclusions: Patients with pre-existing upper airway inflammation, laryngeal symptoms, chemical hypersensitivity, elevated eosinophil/basophil percentages, and pulmonary micro-nodules are more likely to develop chronic post-COVID cough, presenting with partial ventilatory impairment and diffusing capacity impairments. Full article

Chronic obstructive pulmonary disease (COPD) is a major contributor to global respiratory morbidity and exhibits substantial sex- and gender-related differences in incidence, phenotype, pathophysiology, and outcomes across the life course. Historically regarded as a predominantly male disease due to higher smoking rates, COPD is now increasingly recognized among women, reflecting changing exposure patterns and enhanced diagnostic attention. Moreover, evidence indicates that women may be more biologically susceptible to the harmful effects of tobacco smoke and often develop COPD at younger ages. Clinical manifestations also differ, with women more frequently reporting dyspnea, anxiety, and depression, whereas men may exhibit more cough and sputum production. Imaging studies suggest that airway-predominant disease is more common in women, while men are more likely to demonstrate emphysema-predominant patterns. Furthermore, women face an increased risk of exacerbation, yet they are more likely to experience underdiagnosis or misdiagnosis. Treatment responses and comorbidity patterns also show sex- and gender-related variations. Despite these differences, most clinical guidelines and therapeutic strategies do not differentiate by sex and gender, highlighting a gap in personalized COPD management. Overall, growing evidence underscores the importance of incorporating sex and gender as biological and sociocultural variables in COPD research, diagnosis, and treatment. Recognizing sex/gender-specific risk profiles, symptom patterns, and disease phenotypes may improve early detection and enable more targeted, effective interventions. This narrative synthesis, derived from a meticulous search in PubMed and the critical selection of 74 articles from the 448 identified originally, integrates evidence from guideline statements, registry studies, mechanistic and preclinical research, imaging and physiology investigations, systematic reviews, and randomized controlled trials that report sex- and gender-disaggregated data. Full article

Objective: Acute exacerbations (AECOPD) are primary determinants of clinical instability in chronic obstructive pulmonary disease (COPD), and the “frequent exacerbator” (≥2/year) phenotype markedly increases morbidity and healthcare utilization. In this study, we evaluated the association between the Systemic Immune-Inflammation Index (SII), calculated from routine hemogram parameters during the stable period, and the occurrence of frequent exacerbations within the subsequent 1 year, and aimed to define a clinically applicable SII threshold (cut-off). Materials and Methods: In this retrospective observational cohort study conducted at a tertiary care center, patients who attended the outpatient clinic between January 2020 and February 2025 and had COPD confirmed by post-bronchodilator spirometric criteria (FEV₁/FVC < 70%) were identified through electronic medical records. The index date was defined as a routine outpatient visit during stable COPD; patients were followed for AECOPD for 365 days after the index date. The stable period was defined as a visit occurring ≥4 weeks after the last exacerbation and without signs of acute infection. Patients with positive COVID-19 PCR results were excluded due to the uncertainty in distinguishing exacerbation from COVID-19. The primary endpoint was the development of frequent exacerbations (≥2 AECOPD) within 365 days. AECOPD was defined as an acute worsening of dyspnea, cough, and/or sputum requiring additional pharmacotherapy (systemic corticosteroids and/or antibiotics). SII, NLR, PLR, LMR, and PPN were calculated using hemogram parameters. Groups (<2 vs. ≥2 exacerbations) were compared; a ROC–Youden analysis was performed to determine cut-offs. After ROC-based dichotomization, univariate and multivariable logistic regression analyses were used to evaluate associations; multicollinearity was assessed using the VIF. To address potential optimism bias, diagnostic performance metrics (AUC, sensitivity, specificity) were internally validated using 1000 stratified bootstrap replicates. Results: A total of 159 patients were included. The cohort was predominantly male (91.2%). Demographic characteristics and most spirometric parameters were similar between groups; a trend toward lower absolute FVC was observed in the ≥2 exacerbation group (p = 0.051). Platelet counts were higher in the ≥2 exacerbation group (p = 0.029). In the ROC analysis, AUC values ranged from 0.505 to 0.591 across indices. For the SII, the AUC was 0.591 (95% CI: 0.500–0.677; p = 0.049), and the optimal cut-off was 1082.79. The LMR cut-off was 1.76; however, the LMR did not demonstrate statistically significant discriminatory performance in the ROC analysis (AUC 0.535; p = 0.448). In univariate analyses, SII > 1082.79 (OR = 3.028, 95% CI: 1.522–6.027; p = 0.002) was associated with frequent exacerbations. In a multivariable logistic regression adjusted for cardiovascular disease and overall comorbidity status, SII > 1082.79 remained independently associated (OR = 3.029, 95% CI: 1.485–6.179; p = 0.002). Other hemogram-derived indices did not retain independent prognostic significance in this outpatient cohort. Conclusion: SII measured during stable COPD was independently associated with frequent exacerbations over the subsequent 1 year. The SII > 1082.79 threshold may offer a practical risk stratification approach to flag “high-risk” patients in outpatient care. However, given the modest discriminative performance and the single-cohort derivation, this cut-off should be considered exploratory despite the use of bootstrap internal validation. Because this was a single-center study with a predominantly male cohort, the generalizability—particularly to female patients and other settings—requires prospective external validation. Full article

Background/Objectives: The COVID-19 pandemic led to profound lifestyle changes and long-term functional consequences, particularly among individuals with chronic respiratory diseases. Patients with asthma and chronic obstructive pulmonary disease (COPD) may be especially vulnerable to reductions in physical activity and persistent post-COVID-19 symptoms. This study aimed to compare lifestyle characteristics, physical activity levels, and post-COVID-19 symptom persistence in patients with asthma and COPD with those of individuals without chronic disease in the post-pandemic period. Methods: This national, multicenter, cross-sectional study was conducted in 2022 at five pulmonary outpatient clinics. Participants were categorized into three groups: asthma (n = 165), COPD (n = 82), and individuals without chronic disease (n = 431). Demographic and clinical data were collected through face-to-face structured interviews. Physical activity levels were assessed using the short form of the International Physical Activity Questionnaire and expressed as metabolic equivalent of task (MET) scores before and after the pandemic. Dyspnea severity was evaluated using the modified Medical Research Council scale. COVID-19 history, disease severity, and persistent symptoms were recorded. Results: A total of 678 participants were included. The median age was highest in the COPD group (68 (61–74) years), followed by the asthma group (54 (42–64) years) and individuals without chronic disease (38 (27–50) years). Female sex predominated among patients with asthma (77%), whereas male sex was more frequent in the COPD group (83%); sex distribution was similar among individuals without chronic disease (51% female). Across all groups, post-COVID-19 symptoms—including dyspnea, cough, fatigue, and myalgia—persisted for at least six months after infection. Physical activity levels, assessed by metabolic equivalent of task (MET) scores, declined significantly in the post-pandemic period in all groups, with the lowest levels observed in patients with COPD. COVID-19 severity and hospitalization rates were higher in patients with COPD, while intensive care unit admission rates were comparable between patients with asthma and individuals without chronic disease. Conclusions: In the post-pandemic period, physical activity levels declined markedly, and lifestyle changes were negatively affected in patients with asthma and COPD. Post-COVID-19 symptoms persisted longer than expected even in those without chronic disease. Therefore, individualized home-based exercise programs and psychosocial support should be considered to improve physical activity and quality of life, particularly in patients with chronic respiratory diseases, while preventive strategies should also be implemented at the population level. Full article

A chronic cough, defined as a cough persisting for more than eight weeks in adults, is a common clinical problem with a significant impact on patients’ quality of life. This study compares the etiological spectrum and treatment effectiveness of chronic cough in male and female patients. A retrospective analysis was conducted on a cohort of patients diagnosed in the cough clinic between 2017 and 2021. The response to treatment was assessed based on the reduction in cough severity measured using a 100 mm visual analogue scale (VAS). This study included 231 patients: 164 women (70.9%) and 67 men (29.1%). The median duration of cough was 48 months (IQR 24–120). There were no gender differences in age, BMI, smoking history, cough duration, or severity at the initial visit. Upper airway cough syndrome (UACS) and obstructive sleep apnea (OSA) were diagnosed more frequently in men than in women (UACS: 75% vs. 53%, p = 0.002; OSA: 21% vs. 6%, p = 0.001). Cough severity significantly decreased in both groups; the median VAS score dropped from 55 to 40 mm in women (p < 0.0001) and from 69 to 39 mm in men (p = 0.009). The effectiveness of chronic cough treatment, measured by the median reduction in VAS score, was greater in men than in women (32 mm vs. 17.5 mm, p = 0.006). These gender-specific differences in cough etiology and treatment response suggest that a “one-size-fits-all” approach may be inadequate. Full article

Background: Pediatric bronchoscopy and bronchoalveolar lavage (BAL) are valuable procedures, used by pediatric pulmonologists in a wide variety of clinical scenarios. Reports of indications for BAL include investigations of infectious processes, for unusual or poorly responsive pneumonia, and non-infections reasons, including interstitial lung disease and aspiration syndromes. BAL in pediatric asthma is occasionally done in severe and uncontrolled asthma, to rule out co-morbid conditions or to investigate asthma phenotypes. We report here the results of BAL in young children with global pre-BAL diagnoses, with comprehensive analysis of the BAL cellularity and culture results, and with a post hoc review by an allergist. The results of BAL in children with enigmatic pulmonary processes were compared to the expected BAL cellularity in normal children, obtained by an expanded historical mini review. Methods: The initial objective was to perform a mini review of the collective published data for normal/control children with BAL differential cell counts with the purpose of using the results to compare normals to the information obtained on the symptomatic children with BAL results from pulmonologists in our combined allergy–pulmonary division. The exploratory study group was children 0–6 years of age who underwent a BAL from 2000 to 2024 at an academic pulmonary-allergy division. The children had presumptive diagnoses requiring investigation, including the most common diagnoses of asthma, chronic cough, aspiration, or refractory bronchitis, and in this post hoc protocol only the diagnoses provided on the pre- and/or post-operative summary by the divisional pulmonologist(s) performing the BAL were used in the post hoc analysis. Secondarily, the operative day pre- and/or post-lavage diagnoses were used to divide the children into groups (based on operative day diagnoses) to stratify their lavage results, based on eosinophils, neutrophils, culture positivity and lipid-laden macrophages. Normative data collected from the literature was used as the historically expected results for the BAL group(s) analysis. Results: A mini review of BAL cellularity across 25+ years of literature was performed to establish normative data for our subsequent analysis. Both eosinophils and neutrophils are low or absent in normal children based on the comprehensive literature review. As a part of a larger cohort of 500 children ages 0–20 years, 317 children ages 0–6 were selected for review. The protocol was approved by the University Institutional Review Board. Using the mini review as reference, we found that eosinophil counts of one or more were recovered in over 20% of all children, regardless of bronchoscopy indication. Neutrophilia > 50% of cells and/or bacteria colony counts > 100,000 organisms were also frequent findings (>50 percent of the children). As a separate observation, lipid-laden macrophages did not isolate to aspiration indications for the bronchoscopy and lavage. Conclusions: An updated mini review of the cellularity expected in control children provided a context to the findings in our studied exploratory sample population. There was a high recovery of neutrophils coupled with culture positivity found across all children undergoing BAL. Eosinophils > 1 were present in up to 25% with a pre-lavage asthmatic symptom indication, but almost an equal percentage in other children with non-asthma-like conditions was surprising. Lipid-laden macrophage data was unhelpful. Full article

Background: Although diabetes mellitus is traditionally viewed as a systemic metabolic disorder, growing evidence indicates that it also affects the upper airways through vascular, inflammatory, and neuro-sensory mechanisms. The sinonasal mucosa, highly vascularized and immunologically active, may represent an early target of diabetic microangiopathy and immune–metabolic imbalance. Objectives: Our objectives are to synthesize current evidence on the rhinologic manifestations of DM, with a focus on chronic rhinosinusitis, olfactory dysfunction, and other nasal disorders, and to identify the main pathophysiologic and clinical patterns linking diabetes to sinonasal disease. Results: Evidence suggests that DM, particularly type 2 DM, increases susceptibility to CRSwNP and modulates the sinonasal microbiome toward Gram-negative predominance. Surgical outcomes after endoscopic sinus surgery are generally comparable between diabetics and non-diabetics when perioperative care is optimized. Olfactory dysfunction occurs more frequently and severely in diabetic patients, likely reflecting the combined effects of chronic inflammation, vascular compromise, and insulin resistance. Additional manifestations include recurrent epistaxis, delayed mucociliary clearance, and chronic cough. Allergic rhinitis appears to not be increased, and maybe even inversely related, especially among users of DPP-4 inhibitors. Conclusions: Diabetes intersects with rhinologic health through immune–metabolic, vascular, and epithelial pathways that may shape susceptibility, disease phenotype, and neurosensory decline. Future research should focus on disentangling type-specific mechanisms, metabolic biomarkers, and longitudinal outcomes, with the aim of developing precision-based approaches to rhinologic assessment and management in diabetic patients. Full article

Although smoking is the main risk factor for chronic obstructive pulmonary disease (COPD), about one-third of patients have never smoked. This phenomenon supports the idea of a distinct phenotype of the disease in never-smokers, influenced by genetic, infectious, socioeconomic, environmental, and occupational factors. The paper is based on a narrative review of recent literature on the etiology, clinical features, evolution, and therapeutic strategies of COPD in never-smokers, mainly through the analysis of published studies over the last 3 years. COPD in never-smokers occurs predominantly in women, the elderly, and individuals from rural areas or with poor socioeconomic status. Key risk factors include exposure to occupational or environmental pollutants, air pollution, previous respiratory infections, particularly due to pulmonary tuberculosis, and genetic predisposition, mainly through alpha-1 antitrypsin deficiency (A1ATD). Clinically, COPD in never-smokers is characterized by chronic cough and dyspnea, with less severe pulmonary functional impairment, slow progression, and lower prevalence of emphysema compared to smokers. Imaging often highlights bronchiectasis or post-infectious sequelae, and biological markers indicate a significant eosinophilic component. Thus, COPD in never-smokers is a distinct clinical entity with multifactorial pathogenesis and distinct clinical-functional characteristics. Prompt recognition of this form of disease is essential for prevention and adaptation of therapeutic strategies. A personalized multidisciplinary approach can improve disease prognosis and the quality of life for these patients. Full article

Background: Exertional oxygen desaturation (SpO₂ ≤ 88%) during the six-minute walk test (6MWT) is a key prognostic marker in interstitial lung disease (ILD), yet access to the test is often limited in clinical practice. Developing simple, bedside tools to identify patients at risk may support early risk stratification and guide clinical decision-making. Methods: We conducted a retrospective, real-world cohort study in a tertiary referral center between January 2024 and July 2025, including 150 patients, of whom 67.33% (101 patients) were using supplemental oxygen. Clinical and physiological data collected within 30 days of the 6MWT were analyzed. The primary outcome was exertional hypoxemia, defined as peripheral oxygen saturation (SpO₂) ≤ 88% at the end of the test. Four predictive approaches were evaluated: multivariable logistic regression, stepwise logistic regression, and a simplified clinical score (0–3). The simplified score assigned one point for each of the following: forced vital capacity (FVC) ≤ 61% predicted, diffusing capacity for carbon monoxide (DLCO) ≤ 53% predicted, and presence of chronic cough. Model performance was assessed by receiver operating characteristic (ROC) curves, sensitivity, specificity, predictive values, and risk stratification. Results: The simplified score demonstrated robust discriminative performance, comparable to more complex statistical models, with high sensitivity and acceptable specificity. A threshold of ≥2.0 points identified patients at high risk for exertional desaturation with 100% sensitivity and 0.66 specificity. Observed desaturation risk increased progressively across score categories: 17.1% for scores 0–1 (low risk), 58.6% for score 2 (intermediate risk), and 95.1% for score 3 (high risk). Conclusions: Compared with multivariable models, the simplified 0–3 clinical score—based on widely available variables (FVC ≤ 61%, DLCO ≤ 53%, and chronic cough)—maintained similar predictive performance (AUC 0.82) with greater operational simplicity. Owing to its high sensitivity and bedside applicability, it represents a promising screening tool for identifying patients at high risk of exertional desaturation, particularly when the 6MWT is unavailable. Full article

Background: Combined Pulmonary Fibrosis and Emphysema (CPFE) is a distinct syndrome characterized by upper-lobe emphysema and lower-lobe fibrosis, predominantly in older male smokers. Despite often preserved spirometric volumes, patients exhibit severely reduced diffusing capacity and high susceptibility to complications, including pulmonary hypertension (PH), acute exacerbations, and lung cancer, contributing to poor prognosis. Purpose: This review aims to synthesize current evidence on CPFE, focusing on clinical phenotype, functional impairment, differential diagnosis, complications, and emerging management strategies, highlighting distinctions from idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD). Methods: A narrative review of observational cohorts, retrospective series, and clinical studies examining CPFE patients was performed. Data on demographics, smoking history, symptomatology, pulmonary function, radiology, comorbidities, complications, and treatment approaches were extracted and integrated. Results: CPFE affects mainly males aged 65–70, with >90% reporting > 40 pack–years smoking history. Dyspnea is the cardinal symptom (>95%), often disproportionate to preserved FVC and TLC, accompanied by chronic cough in 30–70%. Exercise-induced desaturation is frequent, correlating with PH, observed in 47–90% of patients. Pulmonary function tests reveal preserved volumes, normal or near-normal FEV1/FVC, and severely reduced DLCO (35–45%), distinguishing CPFE from COPD and IPF. HRCT confirms the combined emphysematous and fibrotic pattern, critical for differential diagnosis. Acute exacerbations occur in 20–28% of cases, lung cancer in 22–46% (mostly squamous cell), and long-term oxygen therapy is required in >70%. Five-year survival is 35–55%, lower than emphysema alone and comparable or worse than IPF. Management focuses on smoking cessation, antifibrotics, oxygen therapy, and complication-specific treatments, and selected patients may undergo lung transplantation. Conclusions: CPFE is a clinically and functionally unique entity with a high burden of pulmonary and systemic complications. Accurate recognition using HRCT and DLCO, along with early intervention and tailored management, is essential to improve patient outcomes and guide prognostic stratification. Full article

Hypersensitized P2X3 receptor signaling has been described to play a role in several disorders, including chronic cough. The goal of our in vitro and in vivo studies was to investigate the biotransformation and the influence of CYP3A4 inhibition on the pharmacokinetics of the selective P2X3 antagonist filapixant. Metabolic turnover of filapixant in human liver microsomes and hepatocytes was moderate to high, indicating a complex metabolic pattern with mainly oxidative biotransformation. In recombinant CYP enzymes, depletion of filapixant was observed mainly with CYP3A4 and, to a significantly lesser extent, with CYP1A1, 2D6, 2J2, and 3A5. Drug depletion of [³H]filapixant and metabolite formation in human liver microsomes was significantly inhibited in the presence of strong CYP3A4 inhibitors, whereas other CYP isoform–selective inhibitors showed no or very minor effects. Co-administration of multiple daily doses of 200 mg itraconazole with 80 mg filapixant in humans increased the AUC and C_max of filapixant to 4.01 and 1.89-fold, respectively, indicating that filapixant is a moderately sensitive CYP3A4 substrate. Co-administration of itraconazole also prolonged the half-life of filapixant from 12.1 h to 22.8 h. Overall, changes in AUC, C_max, and half-life indicate that both the bioavailability and elimination of filapixant were affected. Filapixant was well tolerated alone and in combination with itraconazole. Full article

The disease COVID-19, which has befallen mankind in recent years, was a challenge that we had not faced for centuries. The first registered patient case was in China. This review is performed by the inspection of a large body of worldwide investigations conducted in the peak period of the disease’s progress. The disease is spread by airborne droplets and develops mainly with fever, cough, sputum, and shortness of breath. Laboratory tests show leukopenia, lymphopenia, a decrease in the levels of sodium, potassium, and calcium, and an increase in the levels of CRP, LDH, and D-dimer. Radiological changes in most cases are bilateral and of the “ground glass” type in the lower parts of the lungs. The most severe complication of COVID-19 pneumonia is ARDS. The risk groups are people with chronic lung diseases, the elderly, and those who are overweight. This article analyzes and summarizes the main characteristics of SARS-CoV-2 pneumonia in order to better understand and apply better clinical management of this condition. Full article

Background: The reported incidence of pertussis, a vaccine-preventable disease, has been increasing in recent years. This study aimed to estimate the burden of pertussis and the vaccination rate in Australian adults in primary care. Methods: Deidentified data for participants aged ≥18 years were extracted from the MedicalDirector (MD) primary care software from 2008 to 2019. We estimated the cumulative incidence of diagnosed pertussis in adults by age and risk groups and vaccine coverage in cases and a control group (not diagnosed with pertussis or a coughing illness). We also examined the incidence of unspecified coughing illness in the study population. Results: Of the 764,864 subjects included in the study, 1788 (0.2%) were diagnosed with pertussis between 2008 and 2019, corresponding to an average annual diagnosis rate of 76.9 per 100,000 population. About 31,110 (4.1%) of adults had an unspecified coughing illness. The highest rate was observed in 2011 and higher in females (63.3%), and the diagnosis rate was stable across all age groups. Underlying chronic conditions were more prevalent among pertussis cases than controls (58.7% vs. 18.8%), with asthma or chronic obstructive pulmonary disease (COPD) being the most common. Overall, 14% of cases received a pertussis vaccination during the study period. Diagnostic testing for pertussis was performed in 34.1% of pertussis cases. Estimated conservative costs per pertussis patient ranged from AUD 473 to AUD 909, with higher costs observed in individuals with complications. Conclusions: In the outpatient setting, there was a notable burden of pertussis among adults under 65 years of age, particularly those with underlying medical conditions, such as asthma and COPD, which appear to be significant risk factors. Due to the low rate of pertussis testing among all coughing illnesses, a proportion of non-specific coughing illness may be undiagnosed pertussis. The observed low vaccination rates highlight a need for increased awareness, improved diagnostic efforts, and prevention strategies in primary care. Full article