[Neonatal sepsis by Citrobacter Freundii as a debut of cystic lymphatic malformation]

Cystic lymphatic malformation (CLM) is a rare and benign entity caused by alterations in the embryological development of lymphatic structures. Its typical location is in the head and neck, although it has also been described at the abdominal level. It may not be evident in the first stages of life and its first manifestation may be a complication such as abdominal distension, hemorrhage, or sepsis, which may put the patient's life at risk. Surgical treatment is increasingly discussed, and less invasive techniques are proposed.

To describe an uncommon presentation of CLM, radiographic findings, complications, differential diagnosis, and both invasive and more conservative treatments.

Newborn female infant consulted for fever and irritability, without specific signs on physical examination, with suspicion of sepsis. Ultrasonography showed a complex septate mass with cysts of different sizes encompassing the mesenteric vessels, supravesical location. In its most ante rior aspect, it presented a greater echogenicity that corresponded to the superinfected component. Magnetic resonance imaging identified a multitabulated cystic tumor corresponding to a complica ted mesenteric lymphangioma with signs of infection. Due to its size, which compressed the vena cava and the associated signs of complication, complete resection was decided with good subsequent evolution.

The treatment of CLM in pediatric age is increasingly individualized and can vary from surgical resection to less invasive approaches that could reduce acute intraoperative or postoperative complications and mortality. In our case, the infection acted as sclerotherapy, mana ging to delimit the CLM and helping to improve the prognosis.