Acute purulent pericarditis secondary to community-acquired streptococcus pneumonia: A case report

Abstract

BACKGROUND

Pericarditis is the inflammation of the pericardial sac due to a variety of stimuli that ultimately trigger a stereotyped immune response. This condition accounts for up to 5% of emergency department visits for nonischemic chest pain in Western Europe and North America. The most common symptoms of clinical presentation are chest pain and shortness of breath with associated unique electrocardiographic changes. Acute pericarditis is generally self-limited. However, some cases may be complicated by either tamponade or a large pericardial effusion, which carries a significant risk of recurrence. Risk factors for acute pericarditis include viral infections, cardiac surgery, and autoimmune disorders. A rarer cause of pericardial inflammation includes pneumonia, which can induce purulent pericarditis that has been increasingly rare since the advent of antibiotics. Purulent pericarditis carries a high fatality rate, especially in the setting of tamponade, and is invariably deadly without the administration of antibiotics. Bedside transthoracic echocardiogram is a quick and helpful method that can aid in the diagnosis and management.

CASE SUMMARY

We present the case of a 62-year-old woman who sought medical attention at the emergency department (ED) due to a 5-day history of chest pain, shortness of breath, and subjective fevers. Laboratory findings in the ED were significant for leukocytosis and elevated erythrocyte sedimentation rate and C-reactive protein. A chest X-ray revealed a new focal density within the left lower lung base, and a bedside point-of-care ultrasound showed a pericardial fluid collection. The patient was subsequently admitted, where she underwent pericardiocentesis. Fluid cultures from drainage grew streptococcus pneumoniae. She was started on broad-spectrum antibiotics immediately after the procedure. The patient was ultimately discharged in stable condition with cardiology and infectious disease follow-up.

CONCLUSION

This case report emphasizes a unique complication of community-acquired pneumonia. Purulent pericarditis due to streptococcus pneumonia occurs via intrathoracic spread of the organism to the pericardium. This condition is virtually fatal without the administration of antibiotics. Therefore, in the context of suspected pneumonia and a new pericardial fluid collection on imaging, clinicians should suspect purulent pericarditis until proven otherwise, which requires emergent intervention.

Key Words: Purulent pericarditis; Pericardial effusion; Pericardiocentesis; Cardiac tamponade; Streptococcus pneumoniae; Community-acquired pneumonia; Colchicine

Core Tip: Purulent pericarditis is a rare, life-threatening localized infection of the pericardial space that is fatal if left untreated. It is most commonly caused by staphylococcus aureus and streptococcus pneumoniae species. Purulent pericarditis, particularly from community-acquired pneumonia, is a rare occurrence. Diagnosis is commonly obtained via an echocardiogram, and treatment includes pericardiocentesis and antibiotic therapy. This article presents a rare case of purulent pericarditis due to community-acquired pneumonia that was successfully treated.

INTRODUCTION

Pericarditis involves the inflammation of the pericardiac sac surrounding the heart[1]. This condition can be classified as chronic, subacute, and acute, with recurrence occurring in up to 30% of cases[1,2]. It can be complicated by other pericardial syndromes, including pericardial effusion, constrictive pericarditis, and cardiac tamponade, where fluid accumulation in the sac increases the pressure that limits diastolic filling that may result in obstructive shock[3]. Risk factors for acute pericarditis include viral infections, cardiac surgery, autoimmune disorders, radiation, and uremia. Rarely, pneumonia can serve as a cause of purulent pericarditis[1-3]. Streptococcus pneumoniae (S. pneumoniae) can cause localized bacterial pneumonia, resulting in complications such as bacteremia, abscess formation, empyema, and pericarditis[4]. Direct intrathoracic spread of S. pneumoniae into the pericardium is the proposed mechanism of the associated pericardial infection and inflammation[5]. Acute purulent pericarditis secondary to S. pneumoniae is now rarely seen due to the advent of antibiotics[4,5]. Broad-spectrum antimicrobials have decreased mortality rates to 40%[6]. We present a rare case of purulent pericarditis secondary to S. pneumoniae that was treated with drainage and antibiotics. The timely use of bedside echocardiogram, pericardiocentesis, and medication therapy resulted in a good clinical outcome with significant patient improvement on discharge.

CASE PRESENTATION

Chief complaints

Chest pain, shortness of breath, and subjective fevers.

History of present illness

A 62-year-old female presented to the emergency department (ED) due to a 5-day history of pleuritic chest pain, shortness of breathing, subjective fevers, and weakness. She called her pulmonologist to report these symptoms, who subsequently recommended she visit the ED. Upon arrival at the ED, she was afebrile, tachycardic (122/min), and hypotensive (88/45 mmHg). All other vital signs, such as respiration and oxygen saturation, were within normal limits.

History of past illness

Her medical history included Hodgkin’s lymphoma, radiation-induced lung fibrosis, aortic stenosis, acquired hypothyroidism, osteopenia, and severe protein-calorie malnutrition.

Personal and family history

No significant personal or family history.

Physical examination

Physical examination showed an ill-appearing cachectic woman in moderate distress who responded to questions appropriately. S1 and S2 sounds were present, as well as an ejection murmur and friction rub on cardiovascular examination. Lung auscultation revealed decreased breath sounds at the left lower lung base. The abdomen was soft and non-tender to palpation in all quadrants, and extremities were symmetric without pitting edema.

Laboratory examinations

Routine laboratory tests in the ED revealed leukocytosis (white blood cells 19.9/mm³), hypercalcemia (10.5 mg/dL), hyperglycemia (151), hyponatremia (134 mmol/L), lactic acidosis (2.2 mmol/L), elevated troponin (53 ng/L, delta negative), erythrocyte sedimentation rate (126 mm/hr), and C-reactive protein (43.2 mg/dL). All other values, such as coagulation profile, blood gas, liver function tests, and bilirubin levels, were within normal limits.

Imaging examinations

A chest X-ray was done, which showed bilateral pleural calcifications and an increased focal density within the left lower lung base (Figure 1). An electrocardiogram (EKG) was subsequently performed which revealed sinus tachycardia and widespread ST-segment elevation (Figure 2). A bedside point-of-care ultrasound (POCUS) showed a moderate-sized pericardial effusion without evidence of right ventricle or right atrium compression (Figure 3, Video). A computed tomography scan of the chest subsequently revealed similar findings on a bedside echocardiogram. Cardiology was consulted, who recommended admission to Internal Medicine for further management.

Figure 1 Chest X-ray showing bilateral pleural calcifications and left greater than right apical scarring/posttreatment related changes. There is also increased focal density within the left lower lung base, suggestive of consolidation.

Figure 2  Electrocardiogram showing sinus tachycardia with short PR intervals and diffuse ST-elevations (green arrows in lead II).

Figure 3 Parasternal long axis beside cardiac point-of-care ultrasound showing a moderate pericardial effusion (orange arrow) without evidence of right ventricle or right atrium compression. See the video of the point-of-care ultrasound in the emergency department and the official echocardiogram done inpatient.

FINAL DIAGNOSIS

Purulent pericarditis secondary to community-acquired pneumonia.

TREATMENT

The patient was hospitalized, where she was initiated on ibuprofen and colchicine. She subsequently underwent emergent pericardiocentesis 7 hours later, yielding 480 mL of purulent yellow fluid (Figure 4). The patient was started on broad-spectrum antibiotics (vancomycin and ceftriaxone) immediately after her procedure. Fluid analyses were sent where cultures grew S. pneumoniae within two hours.

Figure 4  Two 50 mL syringes showing yellow purulent fluid immediately after pericardiocentesis.

OUTCOME AND FOLLOW-UP

She developed septic shock and atrial fibrillation that required a brief stint in the intensive care unit (ICU) after pericardiocentesis. The patient was transitioned back to the medical floor, where antibiotics were deescalated to ceftriaxone. She was discharged in stable condition on amoxicillin, ibuprofen, and colchicine, with the advice of cardiology and infectious disease follow-up.

DISCUSSION

Acute pericarditis is a condition that involves inflammation of the pericardial sac and accounts for up to 5% of ED visits for non-ischemic chest pain in Western Europe and North America[7]. The incidence in the Western world is approximately 27.7 cases per 100000 people annually[8]. Physical examination can demonstrate findings such as pulsus paradoxus and friction rub[7,8]. However, these are found in less than 50% of patients presenting with an effusion[9]. Laboratory findings such as elevated inflammatory markers can be seen, and EKG findings will show diffuse ST-segment elevation, electrical alternans, PR depression, or low voltage criteria[10]. Risk factors for pericarditis include viral infections, cardiac surgery, connective tissue disorders, renal failure, and neoplasms[9,10]. Rare causes of acute pericarditis include pneumonia, which can induce purulent pericarditis, also known as pyopericarditis[11].

Purulent pericarditis has an incidence rate of approximately 0.005%[5]. It remains a lethal condition due to complications such as septic shock and cardiac tamponade[12]. This form of pericarditis is virtually fatal without treatment with antibiotics. Mortality rates are as high as 100% if left untreated and 40% in treated patients[6,13]. Purulent pericarditis represents a minority of cases, with staphylococcus aureus being the most common isolated organism, followed by S. pneumoniae, Haemophilus influenza, and anaerobes[14]. Intrathoracic spread of the organism to the pericardium in the context of pneumonia is the most common mechanism[5,15]. However, purulent pericarditis secondary to pneumonia is still exceedingly rare, with an approximate incidence of 9% over the past few decades[16,17]. Purulent pericarditis can also occur via hematogenous spread from non-radiologically significant pneumonia or other occult infection[5,14,15].

In this case, our patient had a previous community-acquired pneumonia that likely resulted in the translocation of the bacteria into the pericardium, resulting in her purulent pericarditis. Bedside POCUS immediately identified her pericardial effusion, which was drained promptly. Pericardial fluid cultures were sent, and broad-spectrum intravenous antibiotics were initiated immediately. Although the patient developed septic shock, requiring a brief stint in the ICU, she was discharged in stable condition. The clinical outcome of this case underscores the importance of prompt identification and intervention of suspected purulent pericarditis that is universally fatal if delayed or left untreated. Providers should maintain a high index of clinical suspicion of purulent pericarditis for patients with fever and pericardial effusion on bedside POCUS, as early intervention is crucial to obtain good clinical outcomes.

CONCLUSION

In summary, we report an extremely rare case of purulent pericarditis secondary to community-acquired pneumonia. This case report highlights the attention that should be given to patients who clinically present with fever and a pericardial effusion on bedside ultrasound. Immediate intervention can result in good clinical outcomes in a virtually fatal condition if left untreated.