Information has been received from a health professional concerning a 15 month old female with no allergies or past medical history who on 6/25/01 was vaccinated with a dose of MMRII (lot 639514/0601L). Concomitant vaccination the same day, included the 4th dose of Prevnar and the 4th dose of Hib. On 7/1/01, the pt developed a fever. On 7/4/01, the pt was seen in ER and hospitalized overnight with ataxia, fever and lethargy. The pt underwent a CT scan which was normal and her spinal fluid was reported as normal. The pt was referred to a neurologist and admitted to another hospital on 7/5/01. Subsequently, the pt was discharged on 7/11/01. The health professional reported that the pt was unable to sit unsupported, unable to crawl, unable to ambulate and was at a 9 month old developmental delay. Upon internal review, developmental delay was considered an "Other Important Medical Event". Additional information has been requested. Follow up states: Conflicting follow up information has been received from a health proffessional . It was reported that the pt had recieved her immunizations at the scheduled intervals: these vaccinations included DTaP, HIB conjugate vaccine, hepatitis B vaccine recombinant (yeast), poliovirus vaccine (IPOL), Streptococcus pneumoniae vaccine (Prevnar) and varicella virus vaccine live. The pt was reported as a normal healthy child that had no past medical history of any allergies or problems with vaccinations. The pt was reported to have reached all of her developmental milestones at the appropriate age (i.e walking at 12 months). on 25Jun2001, the pt was in the practice for a 15 month old well visit. It was documentes in the chart that the pt walks, stoops, says 5-6 words at a time, scribbles, follows commands, removes garments when told, and was well at the time of the visit. She was prescribed flouride and was given her first dose of MMR II (lot # 639514/0601?). On 01Jul2001, the pt developed a fever, which the mother treated with acetaminophen ( Tylenol) for 4 days, and the fever resolved. On 04Jul2001, the pt was taken to the hospital becuse she had a fever again that went to 104 degrees, she had decreased Po intake, fussiness, and lethargy. The pt was admitted to the hospital with hypotonia, and the inability to sit. She had a spinal tap done that was resulted as abnormal subcortical white matter, patchy in nature. Her CT scan was done and resulted as degenerative changes of the thoraciac spine. On 05Jul2001, the pt was transferred to another hospital. A neurologist stated that there was a gradual improvement in the pt's muscle tone and coordination when he saw her. The pt was more playful and could prop herself up on her forearms. She had a nasogastric tube due to poor intake, which was removed on 09Jul2001. Early intervention was notified, and the pt was discharged on 11Jul2001 with the diagnosis of cerebellar ataxis. On 15Aug2001, the pt had a follow up visit and it was reported that the pt was making some progress. Results of the CSF were reported as HSV negative. Her acute febrile illness work up was negative. Blood was drawn for antibody titers because the doctor had reported that the pt had MMR II one week prior to her illness. On 27Sep2001, the pt was seen in a neurologist practice. It was reported in her chart that there were no abnormal MMR II titers, and that a MRI would be to determine if there were any inflammatory changes. The pt's most recent visit was on 09Jul2002 by a pediatric neurologist. The physician's assessment was that the pt was 27 months old, post infectious cerebellar ataxia syndrome. She was making slow and steady progress. The pt responds to a pinrick, and has been receiving physical therapy. She was bright, alert, demonstrates improved gait, and improvement with her unsteadiness with some hypotonia. The recommendations were to continue wuth therapies and return in 3 months for a follow up visit. No further information is available.