Typhoid fever is basically a septicaemia / bacteriemia and in cases of generalized septicaemia we get leucopenia due to suppression of bone marrow due to toxin produced

Thanks. But dengue causes both thrombocytopenia and neutropenia why typhoid causes only isolated neutropenia. The precursor for both is same.

Relative lymphocytosis occurs when there is a higher proportion (greater than 40%) of lymphocytes among the white blood cells, while the absolute lymphocyte count (ALC) is normal (less than 4000 per microliter). Relative lymphocytosis is normal in children under age 2.

Yes, relative lymphocytosis and leucopenia are often seen in typhiod fever.  Normalisation of WBC total count and neutropenia are associated with reduction in toxemia and fever.

Sometimes neutropenia may occur when liver markers go up

So while the liver is trying to detoxify the toxins there may be less lymphocytes

My suggestion would be to treat the liver and normalization of lymphocytosis may occur