Paradoxical reaction is defined as documented worsening of signs or symptoms of TB at pulmonary or extrapulmonary sites during appropriate anti TB treatment after initial response to treatment.Paradoxical reaction has been described in HIV negative and HIV positive patients. Use of HAART has increased its frequency. We describe a patient on treatment for TB meningitis who developed acute cerebral edema on the addition of HAART that responded dramatically to steroids.
36 year old male with AIDS on treatment for 7 weeks for TB meningitis and miliary TB with good response, was admitted with worsening mental status. Viral load at initial presentation was 522,000, CD4=31. CT head on diagnosis revealed cerebral edema that resolved by discharge. 10 days before readmission pt was started on HAART. On examination pt was lethargic without focal neurologic deficit but did exhibit bilateral Babinski. CT head showed multiple areas of high density in left thalamus, left frontal lobe with surrounding edema with impending herniation. The patient was mechanically ventilated and was kept on Mannitol, steroids, anti TB, and empiric anti Toxoplasma treatment. At this time viral load had decreased to <400 and CD4 increased to 91. Patient’s neurological status improved dramatically within 24 hours and was weaned off the ventilator. No focal neurological deficits were seen except for old right hemiparesis. MRI done one week later showed meningeal enhancement, no midline shift, no cerebral edema.DISCUSSION: Paradoxical reaction has been described in CNS Tuberculosis especially in patients with low CD4 and high viral load.In patients with CNS Tuberculosis worsening of mental status due to cerebral edema secondary to paradoxical reaction exists especially when HAART is added too early in the course in the course of treatment. The paradoxical reaction is believed to be related to the development of improved Mycobacterium tuberoculosis specific immune responses during the course of anti TB treatment. There is increased proliferation of peripheral blood mononuclear cells, and gamma interferon in response to Mycobacterium tuberculosis specific antigens following HAART in HIV infected patients.
In patients with TB meningitis the possibility of cerebral edema developing due to paradoxical reaction must be considered when deciding the timing of HAART. Recognition of this phenomenon will allow for timely adition of steroids in patients with TB meningitis who exhibit rapid deterioration of CNS function following HAART.
V. Baimeedi, None.