Among the youths referred to our Psychiatric Inpatient Emergency Service, we focused on bipolar disorder (BD), to explore predictive elements for the outcome. Fifty-one patients (30 males, 21 females, age range 8–18 years, mean age 14.2 ± 3.1 years) received a diagnosis of BD, according to historical information, prolonged observations, and a structured clinical interview (K-SADS-PL). Twenty-seven patients (52.9%) were responders at the end of hospitalization according to CGI-I 1 or 2 and 50% decrease of both Brief Psychiatric Rating Scale (BPRS) and Young Mania Rating Scale (YMRS). Responders received a longer hospitalization. Non responders were more severe at baseline, had higher scores at BPRS (namely positive symptoms), and were more aggressive. Environmental/social stressors and comorbidities were frequent, but they did not affect the outcome. In summary, BD in emergency settings may represent a subtype with clinical and therapeutic peculiarities, and specific challenges for mental health services.