In this case, the primary infection was controlled on hospital day 5, as proven by CT evaluation and decreased WBC and PCT levels. The sudden increase in WBC count and decrease in SpO on hospital day 6 were considered to be caused by newly formed septic pulmonary emboli. However, three days were required for diagnosis of LS due to a lack of experience. As a result, anticoagulation therapy was not initiated until hospital day 8, although clinical manifestations appeared on day 6. Interestingly, the WBC count maintained its peak value on hospital days 6-8 before anticoagulation therapy was initiated and decreased instantly after initiation. This kind of change demonstrated that anticoagulation therapy contributed to the antiinflammatory effect achieved by the LS treatment.
In a review of 137 cases of LS, the authors found that 4-6 weeks of carbapenem or piperacillin/tazobactam combined with metronidazole were optimal in terms of antiinflammatory therapy, but the reason for the choice of such a duration was not explained in any of the included papers 5. Our antiinflammatory treatment was performed until the WBC counts remained normal for one week and clinical symptoms improved. The duration was 24 days in total and 16 days after anticoagulation therapy proceeded, which is much shorter than the average. However, it is still unknown whether anticoagulation therapy is essential.
In the past few decades, evidence remains poor regarding the management of LS, particularly regarding its potentially life-threatening thromboembolic complications. Consequently, physicians must make their decisions based on small case series or anecdotal cases when facing uncommon thromboembolic conditions, such as LS. Physicians who are opposed to anticoagulant treatment confirm that the thrombus is caused by an infection process and will be resolved at the same time when the infection is resolved. In contrast, some authors confirm that anticoagulant therapy may reduce the morbidity and mortality of serious complications, such as cavernous sinus thrombosis or pulmonary embolism. Theoretically, a septic thrombus sequesters bacteria and creates a barrier to antibiotic penetration. When the thrombus is dissolved by anticoagulants, the bacteria are exposed to a higher concentration of antibiotics, increasing accessibility 6. Our case supports this hypothesis precisely. Unfortunately, randomized controlled trials are impractical to investigate the use of anticoagulation therapy in the treatment of LS due to the rarity of this illness.
A recent European collaborative study performed an individual patient-level analysis of 712 cases published globally from 2000 to 2017 1. The authors could not find disease-specific elements regarding anticoagulation therapy safety and drew the conclusion that therapeutic anticoagulation is indicated for LS if there are no contraindications. Nevertheless, the authors did not provide definitive guidelines for the duration of anticoagulation. According to the American College of Chest Physicians guidelines for provoked thrombotic events, anticoagulation therapy is recommended for a duration of at least 3 months 7. Our patient received a treatment duration of 20 weeks because his follow-up visit was delayed by the outbreak of COVID-19.
In conclusion, therapeutic anticoagulation may be considered in the management of LS, while further research is needed to evaluate the different outcomes between patients treated with anticoagulants and antibiotics and patients with antibiotics alone.
I’m the daughter of the patient. We are grateful to the doctors’ help in Changzhou First People’s Hospital and happy to share the treatment experience of my farther.