Differential Diagnosis and Workup of Monocytosis: A Systematic Approach to a Common Hematologic Finding

Abstract

Purpose of Review Monocytosis is a frequently encountered clinical condition that needs appropriate investigation due to a broad range of differential diagnoses. This review is meant to summarize the latest literature in the diagnostic testing and interpretation and offer a stepwise diagnostic approach for a patient presenting with monocytosis. Recent Findings Basic studies have highlighted the phenotypic and functional heterogeneity in the monocyte compartment. Studies, both translational and clinical, have provided insights into why monocytosis occurs and how to distinguish the different etiologies. Flow cytometry studies have illustrated that monocyte repartitioning can distinguish chronic myelomonocytic leukemia, a prototypical neoplasm with monocytosis from other reactive or neoplastic causes. Summary In summary, we provide an algorithmic approach to the diagnosis of a patient presenting with monocytosis and expect this document to serve as a reference guide for clinicians.

The Classification of Myeloproliferative Neoplasms: Rationale, Historical Background and Future Perspectives with Focus on Unclassifiable Cases

“…As to the unusual coexistence of driver gene mutations, a JAK2/CALR double-mutated genotype has been reported rarely in MPNs and does not correlate with specific clinical phenotypes [49,52]. Finally, it should be stressed that monocytosis in MPNs is mostly observed alongside fibrotic progression and may be assumed as an indicator of accelerated phase disease [53,54]. This was not the case for our patient.…”

One-step coordination of metal–phenolic networks as antibacterial coatings with sustainable and controllable copper release for urinary catheter applications

“…In addition, relative higher number and percentage of monocytes in the animal's blood of the unmodied catheter group on Day 7 were observed (Fig. S8 †), indicating the animal in the control group had a high risk of monocytosis, 40 probably due to the acute bacterial infections in the animal. The catheter lumen was observed using SEM and the elements deposited on the surface were analyzed (Fig.…”

Monocyte–Lymphocyte Ratio and Dysglycemia: A Retrospective, Cross-Sectional Study of the Saudi Population

“…The monocyte–lymphocyte ratio (MLR) is a simple, inexpensive, and reproducible index of monocyte and lymphocyte counts in peripheral blood. Monocytosis, or elevated monocyte count, is clinically significant in a wide range of conditions including acute and chronic infections, tumors, auto-inflammatory disorders, iatrogenesis, and non-specific stress [ 12 ]. Lymphopenia, or reduced lymphocyte count, is seen in severe combined immunodeficiency [ 13 ], autoimmune disorders such as systemic lupus erythematosus [ 14 ], T2DM [ 15 ], end-stage renal disease [ 16 ], tumors [ 17 ], iatrogenesis, and viral and bacterial infections [ 18 , 19 ].…”