Clinico-pathologic characteristics, updated diagnostic approach and value of positron emission tomography for adults with splenomegaly at a large, university hospital.

Background: Splenomegaly is an important finding in numerous conditions. Most reported cohort studies have not included modern diagnostic methods, such as functional imaging.

Aim: We aimed to determine the utility of newer diagnostic methods and provide an updated approach to splenomegaly by examining recent experience at our centre.

Methods: We conducted a retrospective review of adult patients with splenomegaly of unknown cause using imaging reports over 12 months. We used an upper limit of 13 cm and applied a validated height- and sex-adjusted formula (SplenoCalc) where possible. Data were analysed using Fisher's exact test on Graphpad Prism software.

Results: Liver pathology was identified in 24%, infectious disease in 19%, haematological disease in 18%, inflammatory disease in 8% and no diagnosis in 28%. Patients who had an 18-F-fluorodeoxyglucose positron emission tomography (FDG PET) scan were significantly more likely to undergo a biopsy (25/38 vs. 23/103, P < 0.0001) and reach a diagnosis (34/38 vs. 84/126, P = 0.007). Eight per cent of assessable patients had a spleen size within normal limits when the SplenoCalc formula was applied. Untreated human immundodeficiency virus (HIV) was identified in 8% of tested patients.

Conclusion: In our cohort, PET scanning, where appropriate, was valuable in identifying sites for biopsy and establishing a cause for splenomegaly, particularly haematological or inflammatory. Routine recording of height and use of the SplenoCalc formula in imaging departments may avoid unnecessary investigation of people with normal sized spleens. Due to the prevalence of untreated HIV in our cohort, we would also recommend HIV testing in all patients with splenomegaly.