Viral Infection (e.g., Infectious Mononucleosis): The combination of thrombocytopenia (platelet count of 1 lakh 75 thousand), increased Mean Platelet Volume (MPV), and lymphocytosis (increased WBC with a predominance of lymphocytes) is commonly seen in viral infections. The body's response to the virus can lead to these hematological changes.

Immune Thrombocytopenic Purpura (ITP): Although ITP primarily presents with isolated thrombocytopenia, some cases can have a slightly increased MPV due to the compensatory production of larger platelets. Lymphocytosis might not be a direct feature but can be seen in the context of an immune response.
Chronic Lymphocytic Leukemia (CLL): CLL can present with lymphocytosis and may have associated thrombocytopenia due to bone marrow infiltration or immune mechanisms. An increased MPV can also be observed.
Vitamin Deficiencies (e.g., Vitamin B12 or Folate Deficiency): These deficiencies can lead to thrombocytopenia and increased MPV due to ineffective thrombopoiesis. Lymphocytosis might be less directly related but can occur in the context of a broader bone marrow response.

HIV Infection: HIV can cause a range of hematological abnormalities, including thrombocytopenia, lymphocytosis, and changes in MPV. Given the potential severity and the importance of early diagnosis, HIV should always be considered.
Lymphoma: Both Hodgkin and non-Hodgkin lymphoma can present with lymphocytosis and may have associated thrombocytopenia. An increased MPV can be seen due to bone marrow involvement or paraneoplastic syndromes.
Severe Chronic Diseases (e.g., Chronic Liver Disease, Rheumatologic Diseases): These conditions can lead to thrombocytopenia (e.g., due to splenic sequestration in liver disease) and changes in MPV. Lymphocytosis might be seen in the context of chronic inflammation or immune activation.

Myeloproliferative Neoplasms (e.g., Essential Thrombocythemia): Although these conditions more commonly present with thrombocytosis, rare cases can have thrombocytopenia, especially in the context of other cytopenias or bone marrow fibrosis. An increased MPV can be a feature.
Paroxysmal Nocturnal Hemoglobinuria (PNH): PNH is a rare cause of thrombocytopenia and can have an increased MPV. Lymphocytosis might not be a primary feature but can occur in the context of bone marrow failure.
Congenital Thrombocytopenias: These are rare disorders that can present with thrombocytopenia and often have an increased MPV. Lymphocytosis would be less characteristic but could be seen in specific syndromes.