Misdiagnosis of Community-Acquired Pneumonia

On a follow-up visit to the pulmonologist, she is told that she had a severe case of community-acquired pneumonia (CAP), likely caused by her close work with children. However, the lack of positive cultures for Streptococcus pneumoniae, Haemophilus influenzae, and Legionella pneumophila, common causes of CAP, call this diagnosis into question.

Six months after the resolution of her pneumonia, the patient experiences worsening achalasia symptoms consisting of increased frequency of heartburn and difficulty swallowing, which prompts her to make an appointment with her gastroenterologist.

The physician orders a barium swallow to test her esophageal motility. The results reveal decreased peristaltic functioning of her distal esophagus. In addition, they show increased pressure and tightening of her lower esophageal stricture, as seen by a “bird’s beak” appearance on radiography.4

The gastroenterologist refers the patient to a general surgeon to discuss the possibility of performing a laparoscopic Heller myotomy (LHM) to release the tightened lower esophageal sphincter (LES). Initially, the surgeon is hesitant to consider the procedure because this treatment option usually is reserved for patients with severe achalasia who are at least 60 years of age. Because the LHM procedure loosens the LES, gastroesophageal reflux symptoms can occur. Other complications of the surgery include esophageal perforation and recurrent dysphagia due to incomplete myotomy.5


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Without the surgery, however, the patient likely will continue to live with untreated achalasia, placing her at risk for further episodes of aspiration pneumonia as well as the development of esophageal squamous cell cancer. Although the risk is not absolute, there is a heightened risk for esophageal cancer in patients with achalasia.4 Bacterial overgrowth from trapped food in the esophagus may be a key contributor to chronic esophageal inflammation, worsening achalasia symptoms, and the development of a neoplastic process in the esophagus.6

The patient’s recent history of abrupt-onset dyspnea with rapid progression to hypoxic respiratory failure leads the surgeon to believe that her suspected CAP actually had been a case of aspiration pneumonia. He believes that her worsening achalasia symptoms contributed to her pneumonia. After considering the patient’s entire clinical picture, he decides to carry out the LHM procedure.

The patient responds well to the procedure, and does not have any complications apart from some gastroesophageal reflux symptoms, which are controlled by proton-pump inhibitors. She has had no achalasia-related symptoms of heartburn and dysphagia. Five years later, she has not had any recurrences of aspiration pneumonia.

Aspiration Pneumonia

Aspiration that leads to pneumonia is more commonly thought to result from aspirating a large amount of food, saliva, or fluid. However, clinical research shows that microaspirations have a high chance of resulting in aspiration pneumonia.7 The identified risk factors for aspiration include a history of dysphagia, reduced consciousness, gastric reflux, suppressed cough reflex, a recent surgical procedure in the oropharyngeal region, and intubation. Increased age also is a known risk factor for aspiration because the esophageal muscles and epiglottis weaken with age.8

Patients with known, preexisting conditions that may increase their risk for aspiration need to be made aware of this heightened risk (Table 2).9 To minimize the risk for aspiration, they should be encouraged to eat and drink slowly, chew for at least 30 seconds before swallowing, and tuck the chin to provide support to the esophageal muscles during swallowing. Additional strategies to prevent aspiration include sitting up for at least 3 hours after eating, elevating the head of the bed or sleeping with more pillows, and working with a speech pathologist to improve swallowing techniques.10

In the case presented, the patient had a history of achalasia and mild dysphagia and had been practicing preventive measures such as eating and drinking slowly. Thus, even with precautions, aspiration can occur. Patients at risk should be educated on how rapidly aspiration pneumonia symptoms, such as dyspnea and respiratory failure, can develop, so they know to seek prompt medical intervention. Hospital precautions always should be taken with patients who have been extubated recently or who have a history that puts them at increased risk for aspiration.

Aspiration pneumonia should be considered with any case of rapid-onset pneumonia and rapid progression to hypoxic respiratory failure. This awareness will better direct treatment for patients who need rapid and critical attention.

Paula M. Barrenechea, MPAS, PA-C, is a physician assistant fellow at MD Anderson Cancer Center, in Houston. Stevie M. Redmond, MPA, PA-C, is an associate professor at the College of Allied Health Sciences, Department of Physician Assistant, at Augusta University, in Augusta, Georgia.

References

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2. Khan AN, Sabih A. Aspiration pneumonia imaging. Medscape. January 23, 2016. Accessed August 31, 2020.

3. Le Moal G, Lemerre D, Grollier G, Desmont C, Klossek JM, Robert R. Nosocomial sinusitis with isolation of anaerobic bacteria in ICU patients. Intensive Care Med. 1999;25(10):1066-1071. 

4. Howard PJ, Maher L, Pryde A, Cameron EW, Heading RC. Five year prospective study of the incidence, clinical features, and diagnosis of achalasia in Edinburgh. Gut. 1992;33(8):1011-1015. 

5. Zaninotto G, Costantini M, Portale G, et al. Etiology, diagnosis, and treatment of failures after laparoscopic Heller myotomy for achalasia. Ann Surg. 2002;235(2):186-192. 

6. Nesteruk K, Spaander MCW, Leeuwenburgh I, Peppelenbosch MP, Fuhler GM. Achalasia and associated esophageal cancer risk: what lessons can we learn from the molecular analysis of Barrett’s-associated adenocarcinoma? Biochim Biophys Acta Rev Cancer. 2019;1872(2):188291.

7. Bassis CM, Erb-Downward JR, Dickson RP, et al. Analysis of the upper respiratory tract microbiotas as the source of the lung and gastric microbiotas in healthy individuals. mBio. 2015;6(2):e00037. 

8. Muder RR. Pneumonia in residents of long-term care facilities: epidemiology, etiology, management, and prevention. Am J Med. 1998;105(4):319-330. 

9. Lo WL, Leu HB, Yang MC, Wang DH, Hsu ML. Dysphagia and risk of aspiration pneumonia: a nonrandomized, pair-matched cohort study. J Dent Sci. 2019;14(3):241-247.

10. Fink TA, Ross JB. Are we testing a true thin liquid? Dysphagia. 2009;24(3):285-289.