Although Moraxella catarrhalis was previously considered as a non-pathogenic microorganism, the literature reviewed included a number of diverse infections including neonatal conjunctivitis. The microorganism’s close similarities to Neisseria gonorrhoeae necessitate isolation and correct biochemical differentiation. We report a case of neonatal conjunctivitis misdiagnosed and treated as gonococcal ophthalmia neonatorum based on a Gram stain of the pus discharge showing intracellular gram-negative diplococci. Culture confirmed growth of M. catarrhalis, previously known as Branhamella catarrhalis, which was producing beta-lactamase. This misdiagnosis of gonococcal conjunctivitis carries obvious social, psychological and medical impact. This is probably the first case report from Turkey of neonatal conjunctivitis caused by M. catarrhalis.

Keywords: Moraxella catarrhalis, yenidoğan, psödogonokokal oftalmia neonatorum, neonate, pseudogonococcal ophthalmia neonatorum