History Matters: An Atypical Presentation of Primary Ciliary Dyskinesia in an Adult With Prior Pulmonary Tuberculosis

Abstract Introduction: Primary ciliary dyskinesia (PCD) is a rare, genetic disease characterized by defective ciliary structure and function, leading to impaired mucociliary clearance and recurrent respiratory tract infections. Prevalence rates vary, with estimates ranging between 1 in 16,000 to 20,000 live births. Here, we present a case of a patient with no history of recurrent respiratory infections ultimately diagnosed with PCD. Case presentation:A twenty-nine-year-old man with a history of nasal polyposis, treated pulmonary tuberculosis (TB) three years prior to presentation, and recent emigration to the United States from El Salvador presented to the Zuckerberg San Francisco General Hospital with shortness of breath, fever, and productive cough. Vital signs were notable for heart rate of 139 BPM, temperature 37.9°C, and hypoxia on room air requiring 4L/min of nasal cannula. Physical examination was remarkable for diffuse rhonchi and bibasilar crackles. Laboratory studies were significant for a white blood count of 22.5 cells/μL, ESR 69 mm/h, and CRP 93 mg/L. CT chest (Figure) demonstrated bilateral middle and lower lobe predominant cystic bronchiectasis with mucoid impaction with centrilobular nodules. He was started on broad-spectrum antibiotics while undergoing evaluation for tuberculosis with expectorated acid-fast sputum analysis, which was negative on three smears. His bacterial sputum culture grew Haemophilus influenzae. On consultation with the pulmonary service, it was noted that he had a history of neonatal respiratory distress. Due to this and newly identified bronchiectasis, he was recommended for genetic testing for PCD, which identified two pathogenic variants in DNAH5, a dynein coding gene, confirming the diagnosis of autosomal recessive PCD. Discussion: Given the variability in presentation, symptomatic overlap with other respiratory disorders, and complex diagnostic testing requirements, diagnosis of PCD is often delayed or missed. When correctly diagnosed, age at diagnosis follows a bimodal distribution, with median ages of 5-5.5 years in children and 22 years in adults. Although this patient's pulmonary TB alone could have caused his bronchiectasis, additional history obtained from the patient's mother revealed a history of neonatal respiratory distress, a condition present in approximately 80% of children with PCD. This additional history, coupled with his middle and lower lobe predominant bronchiectasis, raised suspicion for genetic etiologies and prompted further workup that confirmed his diagnosis. This case highlights the heterogeneity of the presentation of PCD and the importance of a thorough history in newly identified bronchiectasis, even in patients who may lack the hallmark symptoms of rare disorders.