Anaemia: conjunctival pallor helped diagnose anaemia.

Clinical bottom line (level 1b)

  1. In medical and surgical patients, presence of conjunctival pallor makes anaemia more likely (LR+4.5) .
  2. Absence of conjunctival pallor makes anaemia slightly less likely (LR-0.61) .
  3. Borderline conjunctival pallor makes anaemia slightly more likely (LR+1.8) .
Sheth et al: Journal of General Internal Medicine 1997; 12: 102-106
Expires June 2003

The study

Setting: tertiary care university hospital, Canada

302 patients (aged mean 57 years, 57% male) medical and surgical in-patients

Excluded if
  • <18 years old
  • not had laboratory measurement of haemoglobin level within three days of clinical assessment
  • transfusion between last blood sample and clinical assessment



    • Independent blinded reference standard, applied in all patients from a consecutive appropriate spectrum.
    Reference standard:
    • haemoglobin level- severe anaemia was defined as = 90 g/l
    Diagnostic test: conjunctival pallor- assessed by at least one of three observers
    • Examination occurred under natural light when possible. If not possible, a small pen flashlight was used.

    The evidence

    pre-test probability of severe anaemia: 18%, (95% CI: 14% to 23%)

    diagnostic test severe anaemia no/borderline anaemia LR+
    (95% CI)    		 post-test probability LR-
    (95% CI)    		 post-test probability
    conjunctival pallor present 8 8 4.5
    (1.8 to 11)     		50% 0.88
    (0.79 to 0.99)     		16%
    conjunctival pallor borderline 22 55 1.8
    (1.2 to 2.7)     		29% 0.77
    (0.62 to 0.97)     		15%
    conjunctival pallor absent 25 184 0.61
    (0.45 to 0.82)     		12% 2.1
    (1.6 to 3.0)     		32%
    total 55 247

    • This physical finding demonstrated good interobserver agreement in this study. The observers were two medical students and one general internist.

    Comments

    1. The absence of conjunctival pallor should not deter one from ordering a hemoglobin determination, if there other clinical reasons to suspect anemia.

    Citation

    1. Sheth TN, Choudhry NK, Bowes M, et al: The relation of conjunctival pallor to the presence of anemia. Journal of General Internal Medicine 1997; 12: 102-106
    Contributor: Clare Wotton and Musab Hayatli, June 2000
    Reviewer: Daniel Sontheimer

    Clinical Question.
    Patient medical or surgical patients
    Intervention or Exposure conjunctival pallor
    Comparison haemoglobin level
    Outcome diagnosis of anaemia