A 3-year-old girl is brought to the urgent care clinic due to chronic cough. The cough began 5 weeks ago and is nonproductive. Three weeks ago, the patient was seen for left lower lobar pneumonia; she completed 10 days of amoxicillin, but the cough has not improved. The patient has mild eczema but is otherwise healthy; her immunizations are up to date. The family had been living in a shelter the previous 2 months but recently moved in with the patient's aunt and her young children. Temperature is 37.1 C (98.8 F). Lung auscultation shows decreased breath sounds on the left with expiratory wheezing. Chest x-ray reveals a left lower lobe infiltrate and hilar adenopathy. Which of the following is the most likely cause of this child's symptoms?

Question

A 3-year-old girl is brought to the urgent care clinic due to chronic cough.  The cough began 5 weeks ago and is nonproductive.  Three weeks ago, the patient was seen for left lower lobar pneumonia; she completed 10 days of amoxicillin, but the cough has not improved.  The patient has mild eczema but is otherwise healthy; her immunizations are up to date.  The family had been living in a shelter the previous 2 months but recently moved in with the patient's aunt and her young children.  Temperature is 37.1 C (98.8 F).  Lung auscultation shows decreased breath sounds on the left with expiratory wheezing.  Chest x-ray reveals a left lower lobe infiltrate and hilar adenopathy.  Which of the following is the most likely cause of this child's symptoms?

Quizplus · Accepted Answer

11ec25c8_d6da_2441_bc81_c195fff323b1_MD0003_00 This patient's chronic cough, focal pneumonia, and hilar adenopathy are consistent with primary pulmonary tuberculosis (TB). TB is most common among children with risk factors for exposure, including traveling from an endemic area, residing in a homeless shelter (as in this case), or having close contact with an infected household member. Similar to patients with secondary (reactivation) TB, children with primary pulmonary TB infection typically have chronic cough or fever of unknown origin (not always present); although chronic cough is generally defined as >8 weeks in adults and >4 weeks in children, even shorter durations (eg, >2 weeks in adults, >3 weeks in children) can raise suspicion for TB in the appropriate epidemiologic and clinical setting. Hilar lymphadenopathy (often reflecting Ghon complex) on chest x-ray is characteristic, and a consolidation or pleural effusion may also be present; unlike with secondary (reactivation) TB, cavitary disease involving the upper lungs is not commonly seen. Lung auscultation can reveal rhonchi, decreased breath sounds, or wheezing in the affected area (possibly due to endobronchial involvement or to compression from surrounding lymphadenopathy). Other nonspecific findings can include fatigue and weight loss or failure to thrive. Unlike in adults, reactivation disease (eg, bilateral upper lung cavitation) is rare in children. primary Screening for TB begins with measuring T-cell response to tuberculin, either via tuberculin skin testing (ie, purified protein derivative) or by an interferon-gamma release assay. Confirmation requires culture of Mycobacterium tuberculosis from sputum samples (older children/adults). Younger children who cannot generate sufficient cough can be tested with early-morning gastric lavage, which recovers M tuberculosis from swallowed tracheal secretions. (Choice A) Asthma can present with chronic cough and diffuse wheezing due to bronchospasm. However, this patient's wheezing is unilateral, and asthma does not cause a focal infiltrate or hilar adenopathy. (Choice B) Foreign body aspiration in young children can cause focal consolidation and wheezing, as well as chronic cough. However, foreign body aspiration does not cause hilar adenopathy. In addition, aspiration is most common in the right lung due to the directionality of the large airways. (Choice C) Mycoplasma pneumoniae causes atypical (eg, bilateral) pneumonia in school-age children. Mycoplasma is not associated with unilateral lung findings or hilar adenopathy. (Choice D) Pneumococcal pneumonia is the most common cause of focal pneumonia in children. However, it is not classically associated with hilar adenopathy, and this patient was treated for pneumococcus with an adequate course of antibacterial therapy, without resolution of symptoms. (Choice E) Respiratory syncytial virus (RSV) is the most common cause of viral bronchiolitis in young children. RSV bronchiolitis presents with diffuse, not focal, wheezing and crackles and rarely lasts longer than 10 days. RSV also does not cause hilar adenopathy. Educational objective: Primary pulmonary tuberculosis (TB) should be suspected in children with chronic cough and characteristic chest x-ray findings (eg, hilar lymphadenopathy, consolidation, pleural effusion), particularly if they have risk factors for TB exposure (eg, homeless shelter). References: Clinical presentation of children with pulmonary tuberculosis: 25 years of experience in Lima, Peru. (http://www.ncbi.nlm.nih.gov/pubmed/25189554) Clinical predictors of culture-confirmed pulmonary tuberculosis in children in a high tuberculosis and HIV prevalence area. (http://www.ncbi.nlm.nih.gov/pubmed/26376315)

A 3-Year-Old Girl Is Brought to the Urgent Care Clinic