Headache caused by and occurring in association with other symptoms and/or clinical signs of a systemic bacterial infection, in the absence of meningitis or meningoencephalitis.
A. Headache of any duration fulfilling criterion C
B. Both of the following:
1. systemic bacterial infection has been diagnosed
2. there is no evidence of meningitic or meningoencephalitic involvement
C. Evidence of causation demonstrated by at least two of the following:
1. headache has developed in temporal relation to onset of the systemic bacterial infection
2. headache has significantly worsened in parallel with worsening of the systemic bacterial infection
3. headache has significantly improved or resolved in parallel with improvement in or resolution of the systemic bacterial infection
4. headache has either or both of the following characteristics:
a) diffuse pain
b) moderate or severe intensity
D. Not better accounted for by another ICHD-3 diagnosis.