CASE 14033 Published on 21.12.2016

Lung Cavitated Lesions in a Drug Addict: think of Septic Emboli



Case Type

Clinical Cases


Teiga, Eduardo; Zuccarino, Flavio; Sánchez, Juan; Carbullanca, Santiago

Hospital del Mar; Passeig Maritim 08005 Barcelona, Spain

25 years, female

Area of Interest Cardiovascular system, Thorax ; Imaging Technique CT
Clinical History
Our patient, with a medical history of heroin-addiction, HCV infection and splenectomy presented to the emergency room disoriented, with hemoptysis and abdominal pain. Findings included tachycardia with normal cardiac sounds, tachypnea, murmurs on auscultation, anemia, leukocytosis, PCR elevation, low platelet count and an acute hypercapnic respiratory failure. Blood culture was positive for S. aureus.
Imaging Findings
Admission chest X-ray ( CXR ) showed ill defined nodular infiltrates in both lung parenchymas, predominantly located in the periphery. At least two of those had a central hypertranslucency related to cavitation. CT showed multiple subpleural nodules and masses in all pulmonary lobes with clearly identifiable feeding vessels. In the right lower lobe there were wedge-shaped densities with ill defined borders caused by septic infarcts. Echocardiography showed a cardiac vegetation on the tricuspid valve. Follow-up CXR showed multiple different-sized nodules reflecting repeated episodes of embolic shower. On subsequent X-ray films those nodules increased in number and changed its appearance ( enlarged size/greater cavitation ). A CXR performed one week later depicted a tension pneumothorax with mediastinal shift, a common complication in the setting of this condition. The patient passed away two weeks after admission with respiratory insufficiency following multiple episodes of bilateral pneumothorax. Barotrauma damage due to mechanical ventilation was presumably its underlying cause.
Septic pulmonary emboli (SPE) refer to embolization of infectious particles into the lungs via the pulmonary arterial system. It’s an uncommon disorder with an insidious onset and difficult diagnosis due to its often nonspecific clinical and radiographic features. Septic emboli can occur from varying sources. The incidence of infective endocarditis as embolic source has sharply declined in recent years presumably due to greater awareness of needle hygiene. Nevertheless, it still represents the main underlying condition of SPE in many medical centers depending on the characteristic of the referral population. The most frequent presenting symptoms include fever, dyspnea, pleuritic chest pain, cough and hemoptysis. Potential sources include bacterial endocarditis, infected central venous catheters, periodontal infections, septic thrombophlebitis, and prosthetic vascular devices. Immunosuppressed patients may be at higher risk of SPE in that their presentation as well microbiological findings may be atypical and / or clinically misleading. The condition is often challenging to diagnose in the absence of a heart murmur or a positive blood culturel. Chest radiographs (CXR) may reveal peripheral poorly marginated lung nodules that have a tendency to form cavities with moderately thick irregular walls. Nodules typically vary in size from 1 to 3 cm (reflecting the repeated episodes of embolic shower) and may increase in number or change in appearance. CRX may also show lower lobe predominant infiltrative densities and accompanying small pleural effusions but findings remain overall nonspecific. CT findings in SPE may include multiple peripheral nodules, feeding vessel sign, pleural-abutting, wedge-shaped peripheral lesions, cavity formation and pleural effusion. Cavitation and feeding vessel represent the more specific findings. CT is more sensitive than CXR in the early phase of the infection, when septic pulmonary emboli appear only as small nodules. Consequently, when CXR findings are negative or equivocal, chest CT is key in SPE detection [1]. Diagnosis is based on characteristic imaging findings in association with one or more of the following criteria: positive blood cultures, tricuspid valve vegetations, a compatible clinical course or other signs of septic embolization. Treatment consists of long-term antibiotics therapy. Management might include mechanical ventilation and tube thoracostomy. For high-risk groups, such as intravenous drug users or patients with intravascular indwelling catheters, fever and imaging findings of multiple nodules or local infiltrates, with or without cavitation, are highly suggestive of SPE. Early diagnosis and prompt antimicrobial therapy or surgical intervention can lead to a successful treatment outcome [2].
Differential Diagnosis List
Pulmonary septic emboli (secondary to tricuspid valve bacterial endocarditis)
Cavitatory pulmonary metastases
Necrobiotic lung nodules
Granulomatosis with polyangitis – Wegener’s Granulomatosis
Final Diagnosis
Pulmonary septic emboli (secondary to tricuspid valve bacterial endocarditis)
Case information
DOI: 10.1594/EURORAD/CASE.14033
ISSN: 1563-4086