The Impact of Renal Tissue Procurement at Bedside on Specimen Adequacy and Best Practices

Bedside Method to Check the Adequacy of Kidney Biopsy Sample with a Smartphone Camera and Macro Lenses: A Prospective Cohort Study

Background

The utilization of smartphone-assisted evaluation is emerging in the field of histopathology. This technique improves the adequacy of samples at the bedside, avoids procedure-related complications, reduces unnecessary repeat biopsies, and saves the cost of the procedure. This study aims to compare the number of glomeruli in a renal biopsy specimen obtained by an ultrasound-guided percutaneous needle biopsy, counted at the bedside using a smartphone fitted with a 16-megapixel macro lens (Bedside method) with that observed under a light microscope after the processing of the biopsy specimen (LM method).

Materials and Methods

In this prospective cohort study, 24 consecutive adult patients (48 kidney biopsy samples) who underwent kidney biopsies were enrolled. All specimens were extracted by an ultrasound-guided percutaneous renal biopsy from the lower pole of the left kidney. Patients' demographics and clinical data were prospectively collected. The number of glomeruli in all the biopsy specimens was counted using a smartphone fitted with a 16-megapixel macro lens at the bedside (Bedside method) and subsequently under a light microscope by a pathologist after processing the biopsy specimen (LM method). Seven or more glomeruli in the specimen were considered adequate in our study.

Results

The mean age of patients at biopsy was 46.9 ± 16 years with slightly male predominance (54.2%). A total of 47 specimens were obtained from 24 patients. Of the 24 patients, 22 had native kidney biopsy and 2 had renal allograft biopsy. The average number of cores obtained per patient was 1.96. The length of core specimens ranged from 1.5 to 2 cm. A good agreement was found between bedside adequacy and slide adequacy, κ =0.684, P = 0.000. The positive agreement rate and negative agreement rate were 91.4% and 23.1%, respectively.

Conclusion

In the modern era of technology, the smartphone is a good tool to evaluate the adequacy of biopsy specimens at the bedside.

Improvement of allograft kidney biopsy yield by using a handheld smartphone microscope as an on-site evaluation device

Background

Smart lens is a magnifying device that turns the smartphone into a microscopic exploring instrument. It is a convenient and inexpensive tool as an on-site evaluation device for the kidney biopsy specimen. We demonstrate the benefit of using a handheld smartphone microscope compared to the standard procedure in allograft kidney specimens.

Material and methods

This was a cohort study of allograft kidney biopsies performed between June 2015 and November 2017 in Srinagarind Hospital, Khon Kaen University, Thailand. The clinical utility of the “Chula smart lens” applied to the smartphone as an on-site evaluation device was studied. Clinical data, diagnostic quality, and complications were retrospectively reviewed and compared between the smart lens group and the standard group.

Results

The study cohort consisted of 93 allograft kidney biopsies (standard:47, smart lens:46). The mean age was 40.6 (18–48) years, and 63 patients (67.7%) were male. By using the smart lens device, the number of obtained tissue cores was higher (3.5 vs 2.9, p = 0.019) and the inadequacy rate for diagnosis was significantly lower (7% vs 21.3%, p = 0.05).

Conclusion

Using a handheld smartphone microscope as an on-site evaluation device resulted in more positive glomeruli and diagnostic yield compared to the standard procedure.