Differential Diagnosis
The provided immunopathology report suggests an abnormal B cell population with clonal expansion. Based on the results, the following differential diagnoses can be considered:
- Single most likely diagnosis
- Chronic Lymphocytic Leukemia (CLL): The presence of clonal B cells with kappa restriction, CD19 and CD20 positivity, and lack of CD5, CD10, CD23, and CD38 expression is consistent with CLL. However, the absence of CD5 expression is atypical for CLL, which often expresses CD5.
- Other Likely diagnoses
- Monoclonal B cell Lymphocytosis (MBL): The clonal B cell population with kappa restriction and normal B cell percentage (11%) could suggest MBL, a condition characterized by the presence of small clones of B cells with a monoclonal immunophenotype.
- Non-Hodgkin Lymphoma (NHL): Although less likely, the clonal B cell population could represent a type of NHL, such as follicular lymphoma or marginal zone lymphoma, which may not always present with typical immunophenotypic features.
- Do Not Miss
- Hairy Cell Leukemia (HCL): Although the report mentions negative CD25 and CD103, which are typical markers for HCL, it is essential to consider this diagnosis due to its potential for severe consequences if missed. HCL can present with atypical immunophenotypic features, and further testing may be necessary to rule out this diagnosis.
- Mantle Cell Lymphoma (MCL): MCL is a type of NHL that can present with a clonal B cell population and atypical immunophenotypic features. It is crucial to consider MCL due to its aggressive nature and potential for rapid progression.
- Rare diagnoses
- Lymphoplasmacytic Lymphoma (LPL): LPL is a rare type of NHL characterized by the presence of clonal B cells with plasmacytic differentiation. Although less likely, it could be considered in the differential diagnosis due to the clonal B cell population and kappa restriction.
- Splenic Marginal Zone Lymphoma (SMZL): SMZL is a rare type of NHL that can present with a clonal B cell population and atypical immunophenotypic features. It is essential to consider SMZL in the differential diagnosis due to its potential for severe consequences if missed.