The phone rings and the lady of the house answers, 'Hello.' 

'Mrs. Sanders, please.'

'Speaking.'

'Mrs. Sanders, this is Doctor Jones at Saint Agnes Laboratory. When your
husband's doctor sent his biopsy
to the lab last week, a biopsy from another Mr. Sanders arrived as well.  We
are now uncertain which one belongs to your husband. Frankly, either way the
results are not too good.'

'What do you mean?' Mrs. Sanders asks nervously.

'Well, one of the specimens tested positive for Alzheimer's and the other
one tested positive for HIV. We can't tell which is which.'

'That's dreadful! Can you do the test again?' questioned Mrs. Sanders.

'Normally we can, but the medical aid will only pay for these expensive
tests one time.' 

'Well, what am I supposed to do now?'

'The folks at the medical aid recommend that you drop your husband off
somewhere in the middle of town
- If he finds his way home, don't sleep with him.'