# Isolated Chronic Neutropenia in Adults: Causes, Diagnostic Work-Up, and Management—A Narrative Review

## TL;DR

This paper reviews the causes, diagnosis, and management of a rare condition called isolated chronic neutropenia in adults.

## Contribution

The paper provides a focused narrative review on non-malignant and non-drug-induced isolated chronic neutropenia in adults.

## Key findings

- Isolated chronic neutropenia is rare and challenging to diagnose due to its varied causes.
- Duffy-null-associated neutrophil count is common in Sub-Saharan Africans and Arabs but not a medical condition.
- Management should be individualized based on clinical history rather than neutrophil count alone.

## Abstract

Neutropenia is certainly of clinical significance due to its increased risk of infections in most patients. Chronic neutropenia is defined as neutropenia that persists for more than 3 months. Isolated chronic neutropenia is rare in clinical practice, and its differential diagnosis can be challenging. This rare entity is the focus of this review. Here, we examine the common causes (drugs, hereditary, autoimmune, and idiopathic), diagnostic work-up, and management of chronic isolated neutropenia in adults. We also discuss the Duffy-null-associated neutrophil count (DANC), which has a high prevalence (80–100%) in Sub-Saharan Africans and in Arabs and is not considered a medical condition. It should be highlighted that management decisions in patients with chronic isolated neutropenia should be individualized, mainly taking into account their clinical history over the neutrophil count alone. In this narrative review, we exclusively focus on non-malignant, non-cytotoxic and non-chemotherapy-induced forms of isolated chronic neutropenia in adults.