Significance of serum delta bilirubin during obstructive jaundice in dogs

A simplified HPLC-based method for measuring unconjugated bilirubin, bilirubin-monoglucuronide, bilirubin-diglucuronide, and delta-bilirubin in plasma with increased conjugated bilirubin

Prolonged icterus is an important and common problem in neonatology and accurate determination of the different bilirubin species, including differentiation between delta-bilirubin and mono- and di-conjugated bilirubin, is useful for diagnostic purposes. However, most bilirubin measurements routinely performed in the clinical laboratory are hampered by the lack of separation of the four bilirubin fractions (unconjugated bilirubin, mono-conjugated bilirubin, di-conjugated bilirubin, and delta-bilirubin). Herein, we propose a high-performance liquid chromatography-based method, independent of commercially available standards or reliable molar absorption coefficients, for the determination of bilirubin fractions in blood samples from icteric patients. The method is a robust and reliable candidate for a semi-automatized setup for measuring the various bilirubin fractions in a specialized laboratory handling samples from clinics with expertise in biliary disease.

Minimally Invasive Cholecystostomy in the Dog: Evaluation of Placement Techniques and Use in Extrahepatic Biliary Obstruction

OBJECTIVE

To evaluate 4 methods of cholecystostomy catheter placement and to report on laparoscopic (Lap) cholecystostomy for the management of extrahepatic biliary obstruction (EHBO) in 3 dogs.

STUDY DESIGN

Experimental study and clinical report.

ANIMALS

Cadaveric dogs (n=20); 2 canine and 1 feline patient.

METHODS

Pigtail cholecystostomy catheters were inserted in 20 canine cadavers using ultrasound (US) or Lap guidance. Insertion routes were either transperitoneal or transhepatic. Methods studied included Lap-transperitoneal, US-transperitoneal, US-transhepatic, and US-Seldinger (n=5 dogs/group). Insertion success, pleural penetration, and insertion site leakage (Lap-transperitoneal group) were evaluated. Three clinical EHBO cases were treated by Lap-transperitoneal technique.

RESULTS

Insertion success was 100% by Lap-transperitoneal but 0% with US-transperitoneal and US-Seldinger methods. US-transhepatic yielded 3 of 5 successful placements. The pleura was penetrated in all US-transhepatic and US-Seldinger insertions. Leakage pressure for Lap-transperitoneal catheters averaged 75 cm H2O (+/-20 cm H2O). Lap-transperitoneal cholecystostomy resulted in marked improvement in 2 dogs, but the catheter became obstructed in the cat. One dog spontaneously regained common bile duct patency and the remaining 2 animals had successful cholecystoenterostomy.

CONCLUSIONS

In cadaver testing, the Lap-transperitoneal cholecystostomy method was superior based on high insertion success with no pleural penetration. In 2 clinical cases, Lap-transperitoneal placement successfully provided biliary drainage for patient stabilization.

CLINICAL RELEVANCE

The role for temporary cholecystostomy has yet to be established, but may aid patient stabilization and mortality reduction in EHBO.

Significance of serum delta-bilirubin in patients with obstructive jaundice

BACKGROUND

Delta-bilirubin is a bilirubin covalently bound with albumin, which is nontoxic and excreted neither in urine nor in bile. We previously reported that the percentage of delta-bilirubin increased after biliary drainage and that the rapidly excretable bilirubin fraction (total minus delta-bilirubin) was a better parameter to predict the effectiveness of biliary decompression in the dog model. The aim of the present study was to elucidate whether it is applicable to humans.

MATERIALS AND METHODS

The serum bilirubin concentration was measured and its fractions were analyzed by high-performance liquid chromatography in 22 patients with obstructive jaundice before and after biliary drainage. In addition, the patients were subgrouped into good and poor drainage groups according to the decline index of serum bilirubin to examine the significance of delta-bilirubin.

RESULTS

The concentration of total bilirubin decreased from 14.1 mg/dl before biliary drainage to 5.4 mg/dl 28 days after drainage. During this period, the percentage of conjugated bilirubin steeply declined from 47.1 to 8.8% and that of excretable bilirubin from 63.4 to 28.6%. In contrast, the proportion of serum delta-bilirubin increased from 36.6 to 71.4%. There was an inverse correlation between percentage of delta-bilirubin and total bilirubin concentration (r = -0.69, P < 0.01). In the good drainage group, the percentage of delta-bilirubin increased above 60% within 7 days after biliary drainage, but it did not reach 60% by 28 days in the poor drainage group. A decreasing rate of total bilirubin minus delta-bilirubin, the excretable bilirubin fraction, was a better index than that of total bilirubin to assess the efficacy of biliary drainage (P< 0.01).

CONCLUSIONS

The increase in the percentage of serum delta-bilirubin indicates an effectiveness of biliary drainage in man. An analysis of serum delta-bilirubin for 7 days can distinguish the good drainage patients from the poor drainage patients.