Felix Wang

The liver-spleen scan as a quantitative liver function test : correlation with liver severity at peritoneoscopy

Sulfur colloid distribution on liver‐spleen scan is determined by the perfused Kupffer cell mass. The perfused Kupffer cell mass is proportional to the perfused hepatocyte mass, but is less affected by acute changes in hepatocyte function. Thus, sulfur colloid distribution parameters (precisely measured by quantitative liver‐spleen scan [QLSS]) may be an excellent test of the perfused hepatic mass. Although no gold standard exists for confirmation, a close correlation should exist between liver disease severity assessed at peritoneoscopy and sulfur colloid distribution. Peritoneoscopy severity (scored as total peritoneoscopy score [PS]; range, 0–5) was assessed in 76 patients who also had QLSS. Multivariate equation were generated to estimate liver disease severity from the QLSS. These were then applied prospectively in 20 consecutive patients to validate these equations. In 76 patients, 62 were evaluated because of chronic liver disease (CLD) and included those with micronodular (20) and macronodular (20) cirrhosis with various degrees of severity (Childs A, 16; B, 29; C, 17). Multivariate analysis yielded a number of combinations of QLSS parameters that correlated with peritoneoscopic severity. These equations were used to estimate liver disease severity. Estimates of liver disease severity (estimated PS [EPS]) correlated well with the PS in these 76 patients (r = .9064; r2 = .8216; P < .0001). Adding histological fibrosis to the QLSS parameters yields an equation for estimating PS that was even more effective (r = .9462; r2 = .8953; P < .001). However, validation of multivariate equations requires confirmation of their value in a second population. Applying these equations to a prospective group of 20 patients who subsequently had peritoneoscopic evaluation produced a similar correlation for QLSS parameters alone for estimating severity (r = .870; r2 = .757; P < .0001), and this was improved when the equation including histological fibrosis was added (r = .936; r2 = .877; P < .001). We believe these data support the QLSS as a quantitative estimate of the perfused hepatic mass that correlates with liver disease severity at peritoneoscopy. (HEPATOLOGY 1995; 22:1113–1121.).

Perfused Kupffer cell mass: Correlation with histology and severity of chronic liver disease

The perfused Kupffer cell mass determines sulfur colloid distribution by liver spleen scan (LSS) and is proportional to the perfused hepatocyte mass. This accounts for the correlation of sulfur colloid distribution with tests of hepatic function and raises the question of whether the LSS can be used as a quantitative test of hepatic function. The recent ability to precisely measure sulfur colloid distribution by single-photon-emission computerized tomography (SPECT) prompted us to evaluate the clinical value in 329 consecutive patients with adequate LSS and clinical information, of which 27 apparent normals and 220 patients with chronic liver disease (CLD) were included in this study. The liver-bone marrow index (LBI) indicated the distribution of counts between the liver and bone marrow. The liver-spleen index (LSI) indicated the distribution between liver and spleen adjusted for spleen size. The LBI and LSI correlated with each other (r=0.753;P<0.001). The arithmetic mean of LBI and LSI was defined as the severity score. Detailed clinical evaluation was available in these patients and included 109 who had liver biopsy. A severity score in 27 normals was 102±5 (mean ±sd) with all values >85. The severity score correlated with hepatic fibrosis (r=−0.694;P<0.001) in 109 patients with benign liver disease who had recent biopsies and with the Child-Pugh classification (r=0.78;P<0.001) in 220 patients with CLD. Furthermore, 68/70 (97%) of patients with ascites, variceal bleeding, or death from hepatic failure had a severity score <85, and all patients with severity score <60 had one of these complications. All patients with liver failure had a severity score <60 and 67.7% with a score <40 died of hepatic failure. By contrast, 99.4% of patients with minimal liver disease had a severity score >80 and 96.5% a severity score >85. Mortality, the frequency of complications of CLD, and the degree of hepatic fibrosis were inversely related to the severity score. Thus, the data support the value of the LSS in detecting the perfused Kupffer cell mass and the potential for use of the LSS as a quantitative test of hepatic function.

Renal Developmental Anomalies

The kidney has a complex origin and some familiarity with its development assists in understanding the numerous congenital disorders of the kidney. Two structures, the ureteric bud and the metanephric blastema, must develop and interact in a normal fashion to produce a normal kidney. The earliest precursor to the adult kidney appears at the end of the third gestational week, when a transient cellular condensation forms the pronephros. This tissue is nonfunctional and soon involutes.