NEEDLE LIVER-BIOPSY IN THALASSEMIA - ANALYSES OF DIAGNOSTIC-ACCURACY AND SAFETY IN 1184 CONSECUTIVE BIOPSIES

We report the reliability and safety of percutaneous liver biopsy in t he evaluation of hepatic iron loading and histology in patients with h omozygous beta-thalassaemia prior to and in serial biopsies following allogeneic bone marrow transplantation for this disorder. 501 thalassa emic patients aged 11+/-4.5 years (range 1-32 years) underwent 1184 co nsecutive percutaneous liver biopsies without ultrasound guidance. Ove rall, 81% of biopsies were evaluable for histological examination and grading of iron, The adequacy of liver biopsy specimens increased with patient age: evaluable specimens were obtained in 73% of patients <5 years of age and in 86% of samples in patients aged >15 years. The deg ree of iron overload and fibrosis in each biopsy was reported separate ly by at least two pathologists who did not know the clinical status o f each patient, In 103 biopsies, iron grade by light microscopy corres ponded to an iron concentration varying between a mean of 32.46+/-14 m u mol/g dry weight liver tissue for iron stores graded by light micros copy as absent to 417.6+/-150 mu mol/g dry weight liver tissue for sto res died following BMT correlated perfectly with that of the first sam ple in >60% biopsies; in most of the discordant cases fibrosis had bee n underestimated in the percutaneous biopsy. Liver biopsy demonstrated evidence of chronic hepatitis in 30% of patients with normal transami nase and in 57% of patients with transaminase within twice the normal range. Liver biopsy was complicated in six patients (0.5%) by haemoper itoneum, periocholecystic haematoma, kidney haematoma, or bile periton itis; no complication was fatal. These data demonstrate that percutane ous liver biopsy provides reliable information regarding liver iron an d histology in homozygous beta-thalassaemia with an extremely low risk of complications.