Benedetta Romanin

Background: Neonatal sepsis caused by multidrug-resistant (MDR) Gram-negative pathogens poses significant therapeutic challenges in neonatal intensive care units (NICUs), particularly in surgical neonates. Ceftazidime-avibactam (CAZ-AVI), a novel β-lactam/β-lactamase inhibitor combination, offers activity against extended-spectrum β-lactamases (ESBLs), AmpC, and serine carbapenemases, but neonatal experience remains limited. Methods and Results: We present a 35-week preterm neonate with long-gap esophageal atresia who developed late-onset sepsis caused by MDR Enterobacter hormaechei, including a KPC-producing carbapenem-resistant isolate, during postoperative recovery. After a multidisciplinary review, the patient received off-label CAZ-AVI at 25 mg/kg/dose (20/5 mg/kg) every 8 h, infused over 2 h, informed by available neonatal pharmacokinetic evidence and weight-adjusted dosing recommendations. Amikacin was administered contextually. Consecutive blood cultures obtained 48–72 h after dual antibiotic therapy initiation became negative and remained sterile, with concordant decline in inflammatory biomarkers, confirming rapid microbiological clearance. Unfortunately, the newborn died in the hours immediately following the final surgery performed to repair the esophageal atresia via end-to-end anastomosis; the cause was complications (hemothorax) unrelated to infectious diseases, although the onset of such severe sepsis may have compromised an already impaired immunological status. Discussion: This case shows mechanism-concordant antimicrobial selection and the feasibility of neonatal dosing when MDR Enterobacterales drive invasive infection. Our experience supports prospective evaluation of CAZ-AVI in carefully selected septic newborns while emphasizing the importance of rapid carbapenemase genotyping, susceptibility testing, and multidisciplinary oversight.

Background: Lemierre syndrome is a rare and life-threatening disease. It is characterized by septic thrombophlebitis of the internal jugular vein, historically associated with Fusobacterium necrophorum infection. However, atypical cases and associations with other organisms have been reported. Methods: Here, we describe a challenging case of Lemierre syndrome in a 71-year-old woman caused by Streptococcus constellatus and review the related literature. Case: The patient experienced multiple hospital admissions due to misdiagnoses and developed thrombosis involving the internal jugular vein and transverse sinus bilaterally, pulmonary complications including the formation of a pseudoaneurysm, and occipital abscess. She presented with headaches, neck pain, and blindness. Prolonged antibiotic therapy was administered, leading to gradual improvement of symptoms, with partial resolution of blindness. Prophylaxis with intramuscular penicillin was prescribed at discharge. Conclusions: Our case underscores the importance of considering Lemierre syndrome in patients who present with multiple thrombotic events affecting the intracranial circulation and/or jugular veins, particularly in those already receiving anticoagulation therapy or with no identifiable cause for thrombosis, even in the absence of sore throat or fever.