A case report of rare complication of brucellosis infection: myocarditis and pneumonitis

Abstract

The involvement of cardiovascular or respiratory complications in cases of brucellosis are extremely rare. Herein, a case of myocarditis and pneumonia with pericardial effusion, pleural effusion and biliteral pleural thickening with pleural adhesion in a 35-year-old female patient, is described. Using next-generation sequencing, the patient was differentially diagnosed with Brucella-related myocarditis and pneumonitis, and treatment with oral doxycycline, rifampicin, and trimethoprim/sulfamethoxazole, along with intravenous gentamycin, was commenced. Following treatment, the patient was clinically improved. When a patient with brucellosis presents with chest pain, clinicians should be aware of this clinical manifestation. Next-generation sequencing may be used to identify pathogens and provide insights into the disease when appropriate cultures are negative.

Introduction

Brucellosis is a zoonosis that may be transmitted to people following direct or indirect contact with infected animals or their products. Brucellosis may affect all organs and systems of the human body. ¹ To the best of our knowledge, in cases of brucellosis, there are few reports of cardiovascular symptoms concomitant with respiratory symptoms. Here, a case of brucellosis in an adult female patient with myocarditis complicated by pneumonitis, is reported.

Case report

A 35-year-old female patient presented at the 940th Hospital of Joint Logistical Support Force of Chinese People’s Liberation Army, Lanzhou, China in March 2022, with a history of fever, fatigue, generalized arthralgia, myalgia for 25 days, productive cough, dyspnoea and chest pain for 3 days. She had a history of close contact with sheep, and had undergone surgical treatment for ventricular septal defect in 2007.

On admission, the patient was in poor general health. Her body temperature was 39.0°C, respiratory rate was 20 breaths/min, heart rate was 80 beats/min, and blood pressure was 120/70 mmHg. Chest auscultation revealed coarse breath sounds and crackles over the inferior zone of the right hemithorax.

Chest computed tomography (CT; Figure 1) showed pneumonia in the right lower lobe, minimal right-sided pleural effusion, biliteral pleural thickening with pleural adhesion, and localized pericardial effusion. Electrocardiography (Figure 2a) showed left-axis deviation with T wave inversions and incomplete right bundle branch block. Abdominal ultrasonography revealed splenomegaly, and transthoracic echocardiography showed the ventricular septal defect repair, normal left ventricular systolic function and range of heart valve thickness.

Figure 1.

Chest computed tomography images from a 35-year-old female patient showing: (a) pneumonia in the right lower lobe of the lungs; (b) localized pericardial effusion (arrow); (c) minimal right-sided pleural effusion (arrow); and (d) pleural thickening with pleural adhesion (found bilaterally).

Figure 2.

Electrocardiography images from a 35-year-old female patient showing: (a) left-axis deviation with T wave inversions and incomplete right bundle branch block at hospital admission prior to antibiotic treatment; and (b) gradually resolving T wave inversions and normalizing heart rate at the 3-month follow-up.

Blood investigations revealed the following: aspartate aminotransferase, 130 IU/L; alanine aminotransferase, 57 IU/L; lactic dehydrogenase, 223 IU/L; hydroxybutyrate dehydrogenase, 313 IU/L; creatine phosphokinase, 179 IU/L; cardiac iso-enzyme of creatine phosphokinase, 310 IU/L; N-terminal brain natriuretic peptide, 439 pg/ml; interleukin-6, 260.9 pg/ml; C-reactive protein, 100 mg/L; and erythrocyte sedimentation rate, 96 mm/h.

Serology results were negative for coronavirus disease 2019, hepatitis B virus, hepatitis C virus, human immunodeficiency virus and Leptospira spp. The Brucella serum agglutination test result was >1/320, however, blood and sputum cultures were negative. In order to identify the pathogen of pulmonary infection, next-generation sequencing (NGS) of bronchoalveolar lavage fluid was performed (outsourced to PACEseq; HUGO Biotechnology Co., Beijing, China), resulting in the detection of 1720 reads (a total of 17,136,183 sequence reads) corresponding to Brucella genus. The patient was diagnosed with Brucella-related myocarditis and pneumonitis. Following verbal informed consent to treatment, 200 mg oral doxycycline (daily for 6 months), 600 mg oral rifampicin (daily for 6 months), one 160/800 mg trimethoprim/sulfamethoxazole oral tablet (twice daily for 6 months), and 320 mg intravenous gentamycin (daily for 4 weeks) were immediately commenced. Following treatment, the patient was clinically improved. Her temperature returned to normal and the chest pain relieved. Electrocardiography (Figure 2b) showed T wave inversions gradually resolved and heart rate gradually normalized at the 3-month follow-up. Pneumonia recovery was shown on the follow-up chest CT at 3 months and 6 months after hospital discharge.

This study was approved by the Ethics Committee of the 940th Hospital of Joint Logistic Support Force of PLA. Written informed consent was obtained from the patient for publication of this case report and any accompanying images. The study conforms to CARE guidelines. ²

Discussion

Brucellosis is a multisystemic disease with many clinical presentations, organ involvements and complications. Involvement of cardiovascular or respiratory complications is extremely rare, with cardiac involvement ranging from 0% to 2%,^3–5 and pulmonary involvement ranging from 0.6% to 10%.^6–9 In the current case, the combined complications of brucellosis myocarditis and pneumonia were diagnosed. To the best of our knowledge, only one case of a patient with combined myocarditis and pneumonia complications has been previously reported in the literature. ¹⁰ The current patient also displayed symptoms of pericardial effusion, pleural effusion and biliteral pleural thickening with pleural adhesion.

In the present case, general symptoms were predominant, but the patient subsequently developed a productive cough, dyspnoea and chest pain. The symptoms of productive cough and dyspnoea appear to be common in patients with pulmonary involvement,^11,12 and chest pain is typical in cardiac involvement.^13,14 Clinicians should remain aware of these symptoms, as such awareness may prevent serious disorders.

Diagnosis of brucellosis requires isolating the organisms from blood or body tissues, or combining the suggestive clinical presentations and positive serology. The efficacy of cultures is significantly decreased with prior use of antibiotics and with subacute and chronic forms of infection. ¹⁵ In the present case, the patient’s blood, sputum and bronchoalveolar lavage fluid cultures were all negative for Brucella species. Brucellosis, especially brucellosis pneumonia, may be confused with many infectious diseases, including tuberculosis. For this reason, NGS of bronchoalveolar lavage fluid was performed, and the Brucella melitensis strains were identified. NGS is a relatively new technique that is increasingly used in the clinical diagnosis of infectious diseases, and several previously published reports have demonstrated the use of NGS as a diagnostic tool for brucellosis.^16,17

Patients with brucellosis myocarditis usually respond well to antibiotic therapy. In the presence of endocarditis, quadruple antibiotic therapy is advised, using doxycycline associated with rifampicin and trimethoprim/sulfamethoxazole for a period of 6 months in combination with gentamycin from 2 to 4 weeks. ¹⁸ The present patient was treated with quadruple antibiotic therapy, although endocarditis had not been found, as she had a history of ventricular septal defect, and myocarditis is considered to be a dangerous complication of brucellosis that is associated with a worse prognosis.

In conclusion, the combination of myocarditis and pneumonia is a highly rare complication of brucellosis. Clinicians should aware of this clinical entity, particularly in areas where Brucella is endemic, because appropriate antibiotic treatment may be life-saving and may prevent the development of serious disorders.