Measuring hemoglobin prior to early discharge without routine surveillance ultrasound after percutaneous native renal biopsy in children

Application value of biopsy through the upper pole of transplanted kidney under the guidance of ultrasound cardiac probe

OBJECTIVE

To investigate the value of needle biopsy of the upper pole of the transplanted kidney guided by the ultrasound cardiac probe.

METHODS

The success rates of biopsy at the upper pole of the transplanted kidney under the guidance of cardiac, abdominal and superficial probes were compared in 540 patients with impaired renal function after renal transplantation. The guidance was completed by an experienced sonographer and the puncture success rate was calculated. Pathologists make the diagnosis and count the success rate of diagnosis and the incidence of complications.

RESULTS

The success rates of puncture of the transplanted kidney under the guidance of the cardiac, abdomen and superficial probe were 100%, 85%,and 73%, respectively, the success rates of pathological diagnosis were 92.68%, 88.9%,and 80.7%, and the incidence of hematoma was 23.2%, 25.3%, respectively, 21.9%, and the pathological diagnosis was mainly acute and chronic rejection.

CONCLUSION

The cardiac probe can clearly guide the puncture through the upper pole of the transplanted kidney, with high guidance success rate and good pathological tissue satisfaction and fewer complications. It is an effective guidance method after renal transplantation.

Predictors of hematoma as a complication in pediatric kidney biopsies

BACKGROUND

Kidney biopsies are crucial in the diagnosis of kidney diseases but they carry the risk of various complications, most commonly hematoma. Here we tried to identify the predictors of hematomas as a complication of kidney biopsies and we constructed an algorithm to stratify the risk.

METHODS

The present report retrospectively reviewed 118 pediatric percutaneous kidney biopsies of native kidneys in 102 children (59 females) with the median age of 9 years (range: 1-19 years) at Kumamoto University Hospital between August 2008 and October 2019. We defined hematoma size using the hematoma index: the short axis of the hematoma/major axis of the kidney on ultrasonography. The inclusion criteria for a hematoma as a complication of a kidney biopsy were hematoma index ≥0.1 and the presence of concomitant, post-kidney biopsy fever or flank pain.

RESULTS

Eight patients presented with a hematoma as a complication. All had hematoma index ≥0.1 and age ≥6 years. On univariate logistic analysis, these patients had a larger hemoglobin (Hgb) decrease on post-biopsy day 1, which was unrelated to a Hgb decrease 2 h after the biopsy, than the patients with no hematoma. All eight patients with a hematoma presented with a fever or flank pain on post-biopsy days 5 to 7, underscoring the need to observe patients with decreased Hgb carefully for about 1 week after a biopsy.

CONCLUSION

Predictors of hematoma as a complication in children after a kidney biopsy were hematoma index ≥0.1, age >6 years, and Hgb decrease ≥15% on post-biopsy day 1.

The utility of post-biopsy ultrasonography in detecting complications after percutaneous liver biopsy in children

BACKGROUND

Surveillance post image-guided percutaneous liver biopsy in children is variable.

OBJECTIVE

The aim of this study was to assess the value of 4-6-h post-procedure ultrasonography (US) in detecting post-liver-biopsy hemorrhage.

MATERIALS AND METHODS

This prospective study included pediatric patients who underwent US-guided percutaneous liver biopsies. All children had a US study obtained pre-procedure and one obtained 4-6 h post-procedure; US examinations were deemed positive if abnormalities were present. We also reviewed any subsequent imaging that was performed within 7 days (late imaging) at the discretion of the referring team. Changes in US findings (ΔUS) were graded by two radiologists using a descriptive non-validated scale (none, minimal, marked). Hemoglobin (Hb) levels were assessed pre-procedure and 4 h post-procedure. The diagnostic accuracy of US changes for detecting post-procedural hemorrhage was calculated based on a drop in Hb >1.5 g/dL or Hb >15% from baseline (ΔHb). We used a Kruskal-Wallis test to correlate the ΔHb with ΔUS. Association between late-imaging and post-procedure US findings was tested using a chi-square test. We included 224 biopsies.

RESULTS

The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of post-procedure US in detecting post-procedure hemorrhage ranged 26.3-42.1%, 72.4-93.3%, 0.22-0.42, and 0.87-0.88, respectively. No significant association was seen between the ΔHb and sonographic findings (P=0.068). No significant difference was seen in the need for late imaging between children who did and those who did not have positive US findings (P=0.814).

CONCLUSION

The sensitivity and PPV of post-procedure US in detecting post-procedural hemorrhage are low. Our findings do not support routine post-procedure surveillance US.

Frequency, Timing, and Prediction of Major Bleeding Complications From Percutaneous Renal Biopsy

Background and Objectives:

The risk and timing of bleeding events following ultrasound-guided percutaneous renal biopsy are not clearly defined.

Design setting, participants, and measurements:

We performed a retrospective study of 617 consecutive adult patients who underwent kidney biopsy between 2012 and 2017 at a tertiary academic hospital in London, Canada. We assessed frequency and timing of minor (not requiring intervention) and major (requiring blood transfusion, surgery, or embolization) bleeds and developed a personalized risk calculator for these.

Results:

Bleeding occurred in 79 patients (12.8%; 95% confidence interval [CI]: 10.4%-15.7%). Minor bleeding occurred in 67 patients (10.9%; 95% CI: 8.6%-13.6%). Major bleeding occurred in 12 patients (1.9%; 95% CI: 1.1%-3.4%); 2 required embolization or surgery (0.3%; 95% CI: 0.09%-1.2%) and 10 required blood transfusion (1.6%; 95% CI: 0.9%-3.0%). Seventy-three of 79 events were identified immediately on post-procedure ultrasound (92.4% of cases; 95% CI: 84.4%-96.5%). Four of 617 patients experienced a minor event not detected immediately (0.6%; 95% CI: 0.3%-1.7%). Two patients (0.3%; 95% CI: 0.09%-1.2%) suffered a major complication that was not recognized immediately; both required blood transfusions only. There were no deaths or nephrectomies. A risk calculator using age, body mass index, platelet count, hemoglobin concentration, size of the target kidney, and whether the kidney is native, or an allograft predicted minor (C-statistic, 0.70) and major bleeding (C-statistic, 0.83).

Conclusions:

This retrospective study of 617 patients who had percutaneous ultrasound-guided renal biopsies supports the safety of short post-biopsy monitoring for most patients. A risk calculator can further personalize estimates of complication risk (http://perioperativerisk.com/kbrc).