Welcome to HCM,
After going through history of your mother was having septicemia
that is infection and required treatment with antibiotics.
This is good that she has responded to treatment and improving.
There are many clinical condition where such rise in urea occurs and creatinine
ratio 20:1 or more.
He blood urea is disproportionately high compared to her creatinine level which is possible in pre renal failure
and sepsis condition,
Please consult a Nephrologist
for proper guidance therapy and with therapy hopefully she will improve in few days.
If her infection is cleared then it is expected that she will improve.
Investigations like Ultrasonography
of abdomen, kidney function,electrolytes,Urine R&M, will guide Nephrologist regarding therapy.
Please Take care
Dr Akhilesh Dubey M.D.