What is the difference between reactive leukocytosis and myeloproliferative disorders in a 57-year-old female with severe abdominal pain?

Subject: Evaluation for Persistent Neutrophilic Leukocytosis with Left Shift/Basophilia – Reactive Process vs Myeloproliferative Disorder Patient Details: 57-year-old female, previously leading a normal active life with no known prior hematological malignancy or chronic systemic illness apart from occasional treatment for diabetes mellitus and hypertension. Past thyroid dysfunction was present many years ago but reportedly normalized later. Weight has remained stable around 70 kg for a long duration. No prior history of chronic fever, recurrent infections, appetite loss, weight loss, abnormal bleeding/bruising, recurrent hospitalizations, lymph node swelling, or known splenomegaly. History of Present Illness: Current illness started suddenly around 2–3 days prior to admission with first-time severe bilateral lower abdominal/groin pain (both iliac/kokh regions), associated with lower back/flank pain and mild breathing discomfort/heaviness. Fever (~100–100.1°F) also appeared for the first time during the same period. Subsequently patient developed marked weakness, dizziness, abdominal tenderness on touch and intermittent fever. No significant urinary burning, retention or major lower urinary tract symptoms were initially reported. BP remained largely stable during admission and patient remained conscious/oriented. Urine Examination: Urine routine microscopy revealed: - Protein ++ - Pus cells: 30–40/hpf - RBCs: 3–4/hpf - Acidic urine - Specific gravity: 1.010 - Urine sugar: Nil Findings were suggestive of urinary tract/kidney inflammatory process. Radiology: Ultrasound whole abdomen showed: - Grade 1 fatty liver - Multiple tiny right renal concretions - 3.1 mm left renal calculus - No significant hydronephrosis or major obstruction reported Hematology/CBC Findings: Initial CBC: - TLC approximately 50,950/cu mm - Neutrophils: 82.9% - ANC: ~42,240 - Hemoglobin: ~10 g/dL - Platelets: previously ~9.39 lakh/cu mm - ESR initially ~35 mm/hr Latest CBC/Hematology: - Hemoglobin: 9.2 g/dL - RBC count: 4.16 million/cu mm - Hematocrit: 30.5% - MCV: 73.3 fL - MCH: 22.1 pg - MCHC: 30.2 g/dL - RDW-CV: 18.3% - TLC: 50,400/cu mm - Neutrophils: 71% - Lymphocytes: 13% - Monocytes: 4% - Eosinophils: 1% - Basophils: 4% - Metamyelocytes: 4% - Promyelocytes: 3% - Platelet count: 5.98 lakh/cu mm - ESR: 62 mm/hr Peripheral Blood Smear (PBS): - Predominantly microcytic hypochromic RBCs with anisocytosis - TLC raised on smear - DLC shows left shift with basophilia - Platelets mildly raised with small platelet clumps - Impression: Microcytic hypochromic anemia with neutrophilic leukocytosis - Advice on report: close hematological follow-up with repeat PBS after control of inflammation/infection to rule out possibility of myeloproliferative disorder Biochemistry: - Serum Creatinine: 0.61–0.66 mg/dL - Serum Urea: 24 mg/dL - SGOT(AST): 22 U/L - SGPT(ALT): 14 U/L - CRP Quantitative: 0.8 mg/L (normal) - Mildly elevated alkaline phosphatase and direct bilirubin noted earlier Viral Markers: - HBsAg: Non-reactive - Anti-HCV: Non-reactive - HIV: Non-reactive Metabolic Findings: During illness, stress hyperglycemia was noted with glucometer readings approximately 235–300+. Current Management: Patient is admitted and receiving antibiotics, hydration, supportive care, antipyretics and symptomatic treatment. Current/recent medications include IV antibiotics initially, followed by Farotuf 200, Dolo 650, Febuxostat 40 mg, Esosan LSR and hydration/electrolyte support. Further Workup: Bone marrow aspiration, bone marrow biopsy and BCR-ABL quantitative testing have now been advised/performed to evaluate persistent neutrophilic leukocytosis with left shift and basophilia. Clinical Query: Kindly review whether the overall presentation appears more consistent with severe reactive leukocytosis/leukemoid reaction secondary to infection/inflammation versus chronic myeloproliferative neoplasm/CML or related hematological disorder, and advise regarding further evaluation and management.