The potential dangers of whooping cough: a case of rib fracture and pneumothorax

Abstract

Background

Pertussis, also known as whooping cough, is an acute respiratory illness primarily caused by Bordetella pertussis. Highly contagious, it poses significant morbidity and mortality risks, especially in infants. Despite widespread vaccination efforts, pertussis cases have recently resurged globally. This case report details possible complication in a 48-year-old woman, involving a cough-induced rib fracture and recurrent pneumothorax, highlighting the need for considering pertussis in patients with severe cough and back pain.

Case presentation

A 48-year-old female non-smoker with hypertension, treated with ACE inhibitor (perindopril), presented with a runny nose, productive cough, and back pain. Initial treatment for a common cold provided temporary relief. However, her symptoms worsened, and further examination revealed a fractured rib, pneumothorax, and subcutaneous emphysema. Laboratory tests confirmed elevated Bordetella pertussis toxin antibodies. She was treated with antibiotics, and despite recurrent symptoms, a conservative management approach was successful. Follow-up indicated resolution of symptoms, but significant anxiety related to her condition.

Conclusion

This case emphasises the importance of considering pertussis in adults, as early symptoms resembling a common cold can lead to misdiagnosis. It also highlights the potential for significant musculoskeletal and pulmonary injuries due to intense coughing associated with pertussis. Prompt diagnosis and comprehensive management, including antibiotics and supportive care, are essential for favorable outcomes.

Background

Pertussis, commonly known as whooping cough, is an acute respiratory illness caused primarily by the bacterium Bordetella pertussis, though Bordetella parapertussis can also be involved. The disease is highly contagious, spreading through droplets produced by coughing or sneezing, and remains infectious up to about three weeks after symptoms begin. Pertussis is a significant cause of morbidity and mortality, particularly in infants younger than two years old.

The disease progresses through three stages over approximately six weeks: catarrhal, paroxysmal, and convalescent, each lasting 1–2 weeks. In the initial catarrhal phase, symptoms resemble a common cold, including nasal congestion, rhinorrhea, sneezing, low-grade fever, tearing, and conjunctival suffusion. The second stage, the paroxysmal phase, is marked by intense attacks of dry coughing, often ending in a characteristic “whoop” sound. This stage can also include post-tussive vomiting and facial redness due to severe coughing. The final convalescent phase is characterized by a persistent chronic cough that can last for weeks, even after other symptoms have resolved [1].

In infants, young children, and chronically ill patients, complications from pertussis can be life-threatening, particularly due to impaired cerebral oxygenation. To battle this, effective vaccines have been developed and widely implemented in national immunization programs since the 1950s and 1960s. The introduction of these vaccines led to a dramatic reduction (over 90%) in pertussis incidence and mortality, particularly among vulnerable populations, such as infants and older adults in industrialized countries [2].

Vaccinated individuals typically experience milder symptoms, and a significantly lower risk of complications compared to the unvaccinated. Additionally, vaccination plays a critical role in reducing the secondary attack rate, which refers to the risk of transmission from an infected person to others. This is important for protecting infants who are too young to be fully vaccinated and adolescents whose immunity may have waned over time.

Despite vaccination efforts, pertussis remains a concern. The American Lung Association emphasizes the importance of starting antibiotic treatment immediately upon diagnosis or suspected exposure. Common antibiotics used include azithromycin, clarithromycin, and erythromycin. While antibiotics have minimal effects on the duration or severity of the disease when administered in the catarrhal phase, and are not proven effective in the paroxysmal phase, their primary role is to reduce disease transmission [3].

Recent epidemiological data from the European Centre for Disease Prevention and Control (ECDC) shows a significant increase in pertussis cases in the EU/EEA, with 25,130 cases reported in 2023 and an additional 32,037 cases from January to March 2024. This surge follows a period of low activity during the COVID-19 pandemic (mid-2020 to end-2022). Historically, from 2012 to 2019, an average of 38,145 cases were reported annually in the EU/EEA, with notable peaks in 2016 and 2019. Similar increases have been reported globally, including in Australia, Brazil, Canada, China, Israel, Montenegro, Serbia, the United States, and the United Kingdom [4].

In the Czech Republic, where our case has been reported, pertussis trends mirror those of the broader EU/EEA, showing significant fluctuations and a recent resurgence (Fig. 1) [5].

Fig. 1.

Number of pertussis cases in the Czech Republic from 2012 to 2024 (*data for 2024 includes only the first three months)

Several factors may explain this uptick, including incomplete vaccination coverage and waning immunity among older populations, particularly adolescents and adults who may not have received booster doses. Additionally, differences in national immunization programs and inconsistent administration of boosters have contributed to higher infection rates in certain regions. Increased laboratory testing and improved reporting practices may also explain part of the rise in detected cases [6].

Another significant factor contributing to the increase in pertussis cases was the COVID-19 pandemic. Disruptions in routine vaccination programs and changes in healthcare access during this time led to a decline in immunity and a decrease in the diagnosis of other respiratory illnesses, resulting in a resurgence of pertussis as social interactions increased [7].

Our case report highlights a possible complication of pertussis: a cough-induced rib fracture and recurrent pneumothorax in an otherwise healthy woman. This underscores the importance of considering pertussis in adults, as early symptoms resembling a common cold can lead to misdiagnosis, especially given the rising number of cases worldwide.

Case presentation

A 48-year-old female non-smoker with a history of arterial hypertension, treated with ACE inhibitors (perindopril), presented to our clinic with symptoms of a runny nose and a productive cough, accompanied by back pain. She had no fever or breathing difficulties. Initially, she was treated for a common cold with mucolytics (erdosteine) and advised to rest and take analgesics for her back pain. Three days later, feeling better, she returned to work.

At her first visit in our clinic, she underwent antigen tests for COVID-19, influenza, and RSV, all of which were negative. At that time, RT-PCR testing was not available at our clinic and pertussis was not yet suspected.

Within a week, the patient came back to our office with worsening back pain, a dry cough, and swelling around her right scapula, extending to her neck. She reported no breathing problems and denied any trauma, falls, or other reasons for her deteriorating condition. Physical examination revealed a large area of subcutaneous emphysema in the right upper back and neck, uneven breath sounds, and crepitation above the emphysema. Her blood pressure and oxygen saturation were normal, but she exhibited tachycardia.

A chest X-ray and subsequent CT scan were performed (Fig. 2), revealing a fractured 9th right rib in the mid-axillary line with lateral displacement, a pneumothorax measuring 45 mm in width, located ventrally and at the apex, with a distance of 15 mm from the pleura, and extensive subcutaneous emphysema. Blood tests were unremarkable except for an elevated CRP level (71 mg/L). The patient was admitted to the ICU of the regional surgery department, where a chest drain was inserted (Fig. 3) for two days to re-expand her lungs and the patient was treated with antibiotics (amoxicillin/clavulanic acid). A non-surgical, conservative approach was selected for managing the rib fracture. Follow-up X-rays after drain removal, after three days of hospitalisation, showed no signs of pneumothorax (Fig. 4). After hospitalization, she was prescribed codeine to help relieve the dry cough and pain, along with recommendations to rest and avoid certain activities that could aggravate her condition.

Fig. 2.

– A, B: CT scans demonstrating a fractured 9th rib with lateral displacement, along with a pneumothorax and extensive subcutaneous emphysema

Fig. 3.

X-ray with an inserted chest drain during the first hospitalisation

Fig. 4.

Follow-up X-ray after drain removal with no signs of pneumothorax

One month later, the patient attended the clinic reporting only a mild cough and no back pain. A few days later, the patient returned to work as an office administrator. After one day of work, her back pain and swelling reoccurred.

Upon examination, another pneumothorax and emphysema were detected on the right side of her chest. She was readmitted to the ICU and later transferred to a university hospital for consultation with the thoracic surgery department. Despite considering surgical intervention for the rib fracture, a conservative approach was chosen. The chest drain was reinserted, and the patient was instructed on breathing exercises. In the absence of an air leak, the chest drain was removed after three days under X-ray guidance, with no signs of pneumothorax recurrence.

Differential diagnosis included osteoporosis, thyroid and parathyroid gland diseases, hematological tumors, and primary and secondary bone tumors. During hospitalization, an abdominal ultrasound showed no pathology, and densitometry revealed osteopenia in both femurs. The FRAX assessment indicated a 4.2% risk of major osteoporotic fracture and a 0.8% risk of hip fracture. Further lab tests revealed elevated Bordetella pertussis toxin antibodies (IgG 350 kU/L, normal < 40 kU/L; IgA 49.8 kU/L, normal < 10 kU/L). The patient was treated with clarithromycin for 10 days.

The patient’s vaccination records are unknown. However, vaccination against pertussis (as part of a combined vaccine for tetanus and diphtheria) has been included in the Czech Republic’s vaccination schedule since 1958. Given that the patient was born in 1976, it is likely she received this vaccine during childhood.

In the beginning, we also considered the possibility of an adverse drug reaction (cough) to ACE inhibitors (ACEIs) in our differential diagnosis. However, since the patient had been on ACEIs for an extended period without previous issues, this diagnosis seemed unlikely.

After discharge, she had a follow-up appointment with a pulmonologist, including a control X-ray and spirometry, both of which were normal. Two months after her second hospitalization, she reported complete resolution of her cough and back pain, though she experienced significant level of anxiety and fear related to her recent health issues.

Discussion and conclusion

Pertussis, or whooping cough, continues to be a significant clinical concern due to its potential to cause severe complications beyond typical respiratory symptoms. In this case, a 48-year-old woman developed a rib fracture and recurrent pneumothorax as a result of Bordetella pertussis infection.

Pertussis is known for causing intense, paroxysmal bouts of coughing, which generate strong pressure changes within the thoracic cavity. Over time, repeated episodes of severe coughing can exert excessive force on the ribs, potentially leading to fractures. This risk is particularly high in individuals with weakened bones, such as the elderly or those with osteopenia or osteoporosis. In cases of rib fracture, the sharp edges of the broken bone can puncture or tear the pleura, leading to complications like pneumothorax.

Other reported causes of pneumothorax include a sudden rise in intra-alveolar pressure: a persistent cough causing such a sudden rise could lead to subpleural bullae or pneumothorax if alveoli rupture.

Similar cough-induced injuries have been described in recent literature. Wang et al. (2022) described a case of multiple rib and vertebral fractures in an elderly patient with pertussis, underscoring the severe mechanical stress that pertussis-induced coughing can impose on the musculoskeletal system. Similar to our patient, who had osteopenia, Wang et al.‘s patient experienced intense coughing that led to fractures, demonstrating that even mild bone demineralization can predispose individuals to significant injuries from pertussis-related coughing [8].

Hanak et al. (2019) from the Mayo Clinic documented multiple instances of cough-induced rib fractures, not all linked to pertussis, but illustrating that severe coughing from any cause can lead to rib fractures [9].

Moreover, complications from pertussis extend beyond rib injuries. Yeung et al. (2021) highlighted that untreated or partially treated pertussis can lead to significant complications, including pneumonia, encephalopathy, and prolonged cough, particularly in vulnerable populations such as infants, older adults, and those with pre-existing conditions. In particular, older adults (≥ 65 years) are at greater risk of rare complications like encephalopathy or stroke. Those with chronic respiratory conditions, obesity, or immunocompromised states are also at higher risk for severe outcomes, such as secondary pneumonia. These risks increase with delayed diagnosis, as early symptoms resembling a common cold can lead to misdiagnosis [10, 11].

This case of a 48-year-old female with pertussis complicated by rib fracture and recurrent pneumothorax underscores illustrates the importance of considering pertussis as a differential diagnosis in adult patients presenting with persistent cough, even if initial symptoms resemble a common cold. Early diagnosis can help prevent complications.

Severe coughing due to pertussis can lead to significant thoracic injuries, such as rib fractures and pneumothorax, especially in individuals with underlying bone conditions like osteopenia.

Increased clinical vigilance is essential in the context of rising global pertussis cases, particularly in adults, to provide timely antibiotic treatment, mitigate transmission, and manage complications effectively.

Author contributions

P.Z. was the treating family physician, collected all patient information, provided follow-up check-ups, and wrote the initial draft of the case report. J.S. reviewed the case report and provided his professional opinion and expert insights. Both authors read and approved the final manuscript.

Funding

No funding was received to assist with the preparation of this manuscript.

Data availability

Availability of data and materials upon request from the main author.

Declarations

Ethics approval and consent to participate

Ethics approval for the case report was provided by the ethics committee of the 3rd Faculty of Medicine, Charles University. The patient gave written informed consent for her personal and clinical details along with any identifying images to be published in this study.

Consent for publication

The patient provided written informed consent for publication, and the manuscript was shared with her for review prior to submission.

Competing interests

The authors declare no competing interests.