Hi and welcome,
IF you didn't have a 24yr MS diagnostic history i would say "increased reflexes in lower limbs" is not usually suggestive-consistent with a neurological condition like MS. Bilateral is generally more suggestive-consistent with structural spinal issues and the peripheral nervous system, which 'could be' connected to your spinal issue/sugery or even connected to any weight issues you also have.
Unilateral is whats more suggestive-consistent of a neurological conditions like MS but after 24 yrs MS is highly likely to of developed into causing bilateral in that time frame.
The main problem i can see as to meaning is IF only the term "increased" has been used, that could actually mean your reflexes are still within the normal range (2+ or 3+)
"deep tendon reflexes are graded as follows:
0 = no response; always abnormal
1+ = a slight but definitely present response; may or may not be normal
2+ = a brisk response; normal
3+ = a very brisk response; may or may not be normal
4+ = a tap elicits a repeating reflex (clonus); always abnormal"
I'm not sure what to make of you recently being told PPMS, if you use to have the relapse-remitting pattern but now you don't, you'd typically be reclassified as Secondary Progressive and not Primary progressive...
PPMS is characterized by worsening neurologic function (accumulation of disability) from the onset of symptoms, without early relapses or remissions.
"One year of disease progression (worsening of neurological function without remission), AND
Two of the following:
A type of lesion in the brain that is recognized by experts in as being typical of MS
Two or more lesions of a similar type in the spinal cord
Evidence in the spinal fluid of oligoclonal band or an elevated IgG index, both of which are indicative of immune system activity in the central nervous system
Meeting these criteria can sometimes take a fairly long time, particularly if the person has only recently begun to experience neurologic symptoms. Several studies have suggested that the PPMS may take two to three years longer to diagnose than relapsing-remitting MS."
It would be pretty unusual after such a long time frame to not have developed multiple neurological abnormalities and higher disability rates by now, so i don't think it's really surprising if the MS neurologist you saw does have concerns that you 'might' have been misdiagnosed with MS back in the 90's.
It's not all that uncommon for pwMS to have their dx questioned and or be undx when they've had to see a new neurologist, all i can suggest is that you look through your historical diagnostic evidence if only for your own peace of mind....
Hope that helps.....JJ
Just to add - increased reflexes in the lower limbs IS consistent with MS. Of course that doesn't mean it's indicative or suggestive. But it IS consistent.
I hope you discover what is truly going on.