Spontaneous pneumomediastinum with concomitant pneumoperitoneum and pneumoscrotum presenting with abdominal pain: A Case Report

Authors

Abstract

IntroductionPneumomediastinum (PM) is defined as the presence of free air within the mediastinum and may be classified as spontaneous, traumatic, or iatrogenic. Spontaneous pneumomediastinum (SPM) occurs in the absence of an identifiable precipitating factor and is generally considered a benign and self-limiting condition. However, atypical presentations may lead to diagnostic uncertainty.
Case PresentationWe report the case of a 47-year-old male who presented to the emergency department with abdominal pain and was found to have SPM associated with pneumoperitoneum and pneumoscrotum due to extensive air dissemination along fascial planes. Comprehensive clinical and radiological evaluation excluded secondary causes, including esophageal perforation. The patient was successfully managed with conservative treatment and close monitoring, resulting in complete clinical and radiological resolution.
ConclusionThis case highlights that SPM may present with unusual manifestations mimicking acute surgical conditions, and emphasizes the importance of accurate diagnosis and appropriate management to avoid unnecessary invasive interventions.

Keywords

Introduction

Pneumomediastinum (PM) is defined as the presence of free air within the mediastinum and may be classified as spontaneous, traumatic, or iatrogenic. Spontaneous pneumomediastinum (SPM) is a rare clinical condition that develops without an identifiable underlying cause, is thought to result from alveolar rupture, and occurs more frequently in males.¹ It is generally considered a benign and self-limiting condition. The underlying mechanism is explained by the Macklin effect, in which air dissects along the bronchovascular sheaths into the mediastinum.² Chest pain and cervical swelling are the most common presenting symptoms. On physical examination, subcutaneous crepitus is the most frequent finding. The diagnosis of SPM is established based on clinical evaluation and radiological imaging, with chest radiography and computed tomography (CT) being the most sensitive diagnostic modalities.³ Although SPM typically follows a benign course, the extension of free air into distant anatomical compartments is rare and may mimic acute surgical conditions, potentially leading to unnecessary invasive interventions.⁴
This report presents a rare case of SPM associated with pneumoperitoneum and pneumoscrotum, presenting with abdominal pain and mimicking an acute abdominal condition.

Case Presentation

A 47-year-old male patient was transferred to the emergency department of our hospital after PM, and free intra-abdominal air was detected at an outside emergency department, where he initially presented with abdominal pain. His medical history revealed a nephrectomy performed ten years earlier and a history of surgery as a liver donor ten months prior to admission.
On physical examination, the patient was in good general condition. Vital signs were as follows: arterial blood pressure 100/65 mmHg, respiratory rate 26 breaths per minute, body temperature 36.8 °C, heart rate 102 beats per minute, and peripheral oxygen saturation (SpO₂) 97%. Head and neck examination revealed palpable crepitus consistent with subcutaneous emphysema, predominantly in the cervical region. Chest examination demonstrated palpable crepitus. Cardiovascular examination was unremarkable, and Hamman’s sign was not detected.
On abdominal inspection, the abdomen appeared distended; however, no rebound tenderness or guarding was noted. Testicular examination revealed bilateral scrotal enlargement secondary to diffuse subcutaneous emphysema, measuring approximately 10 × 8 cm. Diffuse subcutaneous emphysema was also noted in the gluteal region. Laboratory investigations revealed a white blood cell count of 16.07 × 10³/µL, hemoglobin level of 15.3 g/dL, platelet count of 168 × 10³/µL, neutrophil count of 13.51 × 10³/µL (84.1%), and a C-reactive protein level of 94.17 mg/L.
Chest radiography demonstrated mediastinal emphysema, diffuse subcutaneous emphysema in the cervical region, and air beneath the diaphragm (Figure 1). Based on a comprehensive evaluation of the patient’s medical history, physical examination findings, laboratory results, and imaging studies, the patient was diagnosed with PM, pneumoperitoneum, and pneumoscrotum and was admitted to the thoracic surgery service. Given the presence of free air in multiple compartments, invasive causes such as esophageal perforation and intra-abdominal visceral perforation were actively excluded through a multidisciplinary diagnostic approach. Following multidisciplinary evaluation involving the departments of Otolaryngology and General Surgery, the patient underwent sequential imaging and diagnostic procedures, including cervical CT, total abdominal ultrasonography, scrotal ultrasonography, and endoscopy. No pathological findings were detected on otolaryngologic examination or endoscopic evaluation.
Thoracic CT revealed diffuse air collections surrounding the heart, mediastinal vascular structures, trachea, and esophagus, consistent with severe PM (Figure 2). Cervical CT showed widespread air collections between the muscular planes and within the subcutaneous tissues (Supplementary Figure 1). Whole abdominal CT demonstrated diffuse intraperitoneal free air (Supplementary Figure 2). Pelvic CT revealed extensive air collections in the perivesical and perirectal regions, within the retroperitoneal space —particularly surrounding the left psoas muscle—and into the subcutaneous tissues of the scrotum, sacral, and coccygeal regions (Supplementary Figure 3 and Figure 3). On esophageal CT with oral contrast, no evidence of contrast extravasation was detected (Supplementary Figure 4).
Following further multidisciplinary evaluation involving the departments of Otolaryngology and General Surgery, additional diagnostic procedures, including whole abdominal ultrasonography, scrotal ultrasonography, esophagogastroduodenoscopy, and flexible bronchoscopy, were performed. No pathological findings suggestive of perforation or airway injury were identified (Supplementary Figure 5 and Supplementary Figure 6).
Based on the absence of trauma history and the lack of an identifiable etiological focus despite comprehensive evaluation, the patient was diagnosed with SPM associated with pneumoperitoneum and pneumoscrotum. The patient was admitted to our thoracic surgery clinic, where medical treatment was initiated, and close monitoring was performed.
Medical management included antibiotic therapy, expectorants, and nasal oxygen supplementation. Empirical broad-spectrum antibiotic therapy was initiated due to the potential risk of mediastinitis despite the absence of a confirmed infectious source. Oral intake was discontinued on the first day. During follow-up, the patient showed clinical improvement, with regression of the widespread subcutaneous emphysema. Daily physical examinations and investigations were conducted to monitor for possible mediastinal and intra-abdominal complications. On the second day, oral intake was resumed with a liquid diet.
Follow-up thoracic and abdominal CT scans demonstrated radiological regression, while laboratory parameters, including white blood cell count and C-reactive protein levels, returned to normal ranges. By the fifth day, complete resolution of the generalized subcutaneous emphysema was observed clinically. The patient was discharged in good condition on the sixth day. At the outpatient follow-up visit on the tenth day, the patient reported no active complaints, physical examination revealed no pathological findings, and both imaging and laboratory studies were within normal limits.
The clinical course can be summarized as follows: on Day 1, the patient was admitted and underwent comprehensive imaging and diagnostic evaluation; on Day 2, oral intake was resumed following clinical stabilization; by Day 5, complete clinical resolution of subcutaneous emphysema was achieved, and the patient was discharged on Day 6 with full recovery confirmed at follow-up.
This case highlights the importance of prompt diagnosis, appropriate treatment, and early planning to prevent potentially serious complications in patients with SPM. With this case report, we aim to contribute to the existing literature.
Ethical ApprovalThis study did not require ethical approval according to the relevant guidelines.
This case is reported in accordance with the Case Report Guidelines (CARE) guidelines.

Discussion

SPM is primarily explained by alveolar rupture secondary to increased intra-alveolar pressure, followed by air dissection along the bronchovascular sheaths into the mediastinum, a process known as the Macklin effect.^2,5 This mechanism is the most widely accepted pathophysiological explanation for SPM.
Conditions such as asthma, chronic obstructive pulmonary disease, coughing, vomiting, straining, excessive physical exertion, and substance use may predispose to SPM by increasing intra-alveolar pressure.^2,5,6 However, some patients present without an obvious triggering factor.
After accumulating in the mediastinum, air may further extend along fascial planes into adjacent anatomical compartments. Although this dissemination pattern is recognized, simultaneous involvement of distant compartments such as the peritoneal cavity and scrotum remains rare.⁴
Patients with SPM most commonly present with chest pain, cervical swelling, dyspnea, or subcutaneous emphysema.^2,5,6 However, atypical presentations may occur depending on the extent and distribution of free air. In particular, pneumoperitoneum may lead to abdominal pain and mimic acute surgical conditions, potentially resulting in unnecessary invasive interventions.
CT is the gold standard for diagnosis because it allows accurate visualization of mediastinal air and helps exclude secondary causes such as esophageal perforation.⁷ In the present case, the extensive distribution of free air required a comprehensive diagnostic evaluation, including contrast-enhanced imaging, endoscopy, and bronchoscopy, to rule out life-threatening etiologies.
Although SPM is generally benign and self-limiting, serious complications such as mediastinitis must be considered in selected cases. Therefore, prompt diagnosis and close clinical monitoring remain important. Once secondary causes are excluded and the patient is clinically stable, conservative management may be considered.^5,6,8 Most patients show rapid clinical and radiological improvement with supportive treatment.
Our case is notable for the simultaneous presence of pneumomediastinum, pneumoperitoneum, and pneumoscrotum in the absence of trauma or iatrogenic causes. Such presentations may closely mimic acute abdominal pathology and lead to unnecessary surgical exploration if not correctly recognized. Therefore, awareness of this rare clinical entity and careful clinical and radiological assessment are essential for appropriate management.

Limitations

This report is limited by its single-case design, which restricts the generalizability of the findings. Additionally, the absence of long-term follow-up data prevents assessment of potential late complications or recurrence. Further studies, including larger case series, are needed to better define the clinical spectrum and optimal management strategies of this condition.

Conclusion

SPM is a rare but generally benign condition that may present with atypical findings and mimic acute surgical emergencies. Accurate diagnosis relies on careful clinical assessment and CT to exclude life-threatening secondary causes such as esophageal perforation. In this case, after secondary etiologies were excluded, conservative management was sufficient and resulted in a favorable outcome. Early recognition of this condition is essential to avoid unnecessary invasive interventions.

Declarations

Abbreviations

CT: Computed tomography
PM: Pneumomediastinum
SPM: Spontaneous pneumomediastinum

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About This Article

Received:

April 3, 2026

Accepted:

June 24, 2026

Published Online:

June 24, 2026