Warning

Normal lymphocyte count range 1.5 – 3.5X109/L

Severe lymphopenia: lymphocyte count < 0.5

Mild lymphopenia: lymphocyte count 1.0 – 1.5

Lymphopenia is a common non-specific finding. It increases in frequency with advanced age and increasing co-morbidities. In most cases it is a transient condition and does not require specialist input.

Causes

  • Infection - HIV, acute bacterial infection, Hepatitis B/C
  • Medication - steroid (including inhaled), chemotherapy, monoclonal antibodies, immune-suppressant drugs
  • Systemic disorders - auto-immune conditions, renal failure, sarcoidosis, inflammatory bowel disorders
  • Neoplastic - solid organ malignancy, Lympho-prolifertative disorders
  • Alcohol excess, malnutrition, radiotherapy, stress , exercise
  • Congenital immune disorders

Assessment

  • History and examination - oral thrush, adenopathy or organomegaly, features of systemic disease
  • Inflammatory markers - ESR/CRP
  • HIV, viral hepatitis serology
  • Auto-immune screen

Who to refer

  • Presence of B Symptoms
  • Adenopathy of >1 cm or Splenomegaly

Who not to refer

Referral is not indicated in cases of isolated lymphopenia in an otherwise well patient with normal examination and negative investigations. Recommend repeating FBC in 6 months, if no change then no further monitoring is required

Editorial Information

Last reviewed: 01/10/2024

Next review date: 01/10/2026

Author(s): Muayed Lasebai, Ranjit Thomas, Paul Ames.

Version: 1.0