Acalculous disease of the gall bladder

A Pointwise Method for Identifying Biomechanical Heterogeneity of the Human Gallbladder

Identifying the heterogeneous biomechanical property of human gallbladder (GB) walls from non-invasive measurements can have clinical significance in patient-specific modeling and acalculous biliary pain diagnosis. In this article, a pointwise method was proposed to measure the heterogeneity of ten samples of human GB during refilling. Three different points, two on the equator of GB body 90° apart and one on the apex of GB fundus, were chosen to represent the typical regions of interest. The stretches at these points were estimated from ultrasound images of the GB during the bile emptying phase based on an analytical model. The model was validated against the experimental data of a lamb GB. The material parameters at the different points were determined inversely by making use of a structure-based anisotropic constitutive model. This anisotropic model yielded much better accuracy when compared to a number of phenomenologically-based constitutive laws, as demonstrated by its significantly reduced least-square errors in stress curve fitting. The results confirmed that the human GB wall material was heterogeneous, particularly toward the apex region. Our study also suggested that non-uniform wall thickness of the GB was important in determining the material parameters, in particular, on the parameters associated with the properties of the matrix and the longitudinal fibers—the difference could be as large as 20–30% compared to that of the uniform thickness model.

Acute cholecystitis associated with infection of Enterobacteriaceae from gut microbiota

Acute cholecystitis (AC) is one of the most common surgical diseases. Bacterial infection accounts for 50% to 85% of the disease's onset. Since there is a close relationship between the biliary system and the gut, the aims of this study were to characterize and determine the influence of gut microbiota on AC, to detect the pathogenic microorganism in the biliary system, and to explore the relationship between the gut and bile microbiota of patients with AC. A total of 185 713 high-quality sequence reads were generated from the faecal samples of 15 patients and 13 healthy controls by 16S rRNA gene pyrosequencing. Patients' samples were significantly enriched in Akkermansia, Enterobacter and Escherichia/Shigella group. The healthy controls, however, showed significant enrichment of Clostridiales, Coprococcus, Coprobacillaceae, Paraprevotella, Turicibacter and TM7-3 in their faecal samples. Escherichia coli was the main biliary pathogenic microorganism, among others such as Klebsiella spp., Clostridium perfringens, Citrobacter freundii and Enterobacter cloacae in the bile of the patients. Additionally, the amount of bile endotoxin significantly correlated with the number of Enterobacteriaceae, especially E. coli. Our data indicate that Enterobacteriaceae might play essential role in the pathogenesis and/or progress of AC. This was verified in an in vivo model using a pathogenic E. coli isolated from one of the patients in guinea pigs and observed marked gallbladder inflammation and morphologic changes. This study thus provides insight which could be useful for the prevention, diagnosis and treatment of AC and related diseases by controlling the growth of Enterobacteriaceae to alleviate the infection.

TG13 current terminology, etiology, and epidemiology of acute cholangitis and cholecystitis

While referring to the evidence adopted in the Tokyo Guidelines 2007 (TG07) as well as subsequently obtained evidence, further discussion took place on terminology, etiology, and epidemiological data. In particular, new findings have accumulated on the occurrence of symptoms in patients with gallstones, frequency of severe cholecystitis and cholangitis, onset of cholecystitis and cholangitis after endoscopic retrograde cholangiopancreatography and medications, mortality rate, and recurrence rate. The primary etiology of acute cholangitis/cholecystitis is the presence of stones. Next to stones, the most significant etiology of acute cholangitis is benign/malignant stenosis of the biliary tract. On the other hand, there is another type of acute cholecystitis, acute acalculous cholecystitis, in which stones are not involved as causative factors. Risk factors for acute acalculous cholecystitis include surgery, trauma, burn, and parenteral nutrition. After 2000, the mortality rate of acute cholangitis has been about 10 %, while that of acute cholecystitis has generally been less than 1 %. After the publication of TG07, diagnostic criteria and severity assessment criteria were standardized, and the distribution of cases according to severity and comparison of clinical data among target populations have become more subjective. The concept of healthcare-associated infections is important in the current treatment of infection. The treatment of acute cholangitis and cholecystitis substantially differs from that of community-acquired infections. Cholangitis and cholecystitis as healthcare-associated infections are clearly described in the updated Tokyo Guidelines (TG13). Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

Cross-bridge apparent rate constants of human gallbladder smooth muscle

This paper studies human gallbladder (GB) smooth muscle contractions. A two-state cross-bridge model was used to estimate the apparent attachment and detachment rate constants, as well as increased Ca2+ concentration from the peak active stress during the isometric contraction. The active stress was computed from a mechanical model based entirely on non-invasive routine ultrasound scans. In the two-state cross-bridge model, the two apparent rate constants, representing the total attached/detached cross-bridges, respectively, were estimated using active stress prediction for 51 subjects undergoing cholecystokinin-provocation test, together with estimates from the four-state cross-bridge model for a swine carotid, bovine tracheal and guinea pig GB smooth muscles. The study suggests that the apparent rate constants should be patient-specific, i.e. patients with a lower stress level are characterized by smaller apparent rate constants. In other words, the diseased GB may need to develop fast cycling cross-bridges to compensate in the emptying process. This is a first step towards more quantitative and non-invasive measures of GB pain, and may provide useful insight in understanding GB motility and developing effective drug treatments.

Definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis: Tokyo Guidelines

This article discusses the definitions, pathophysiology, and epidemiology of acute cholangitis and cholecystitis. Acute cholangitis and cholecystitis mostly originate from stones in the bile ducts and gallbladder. Acute cholecystitis also has other causes, such as ischemia; chemicals that enter biliary secretions; motility disorders associated with drugs; infections with microorganisms, protozoa, and parasites; collagen disease; and allergic reactions. Acute acalculous cholecystitis is associated with a recent operation, trauma, burns, multisystem organ failure, and parenteral nutrition. Factors associated with the onset of cholelithiasis include obesity, age, and drugs such as oral contraceptives. The reported mortality of less than 10% for acute cholecystitis gives an impression that it is not a fatal disease, except for the elderly and/or patients with acalculous disease. However, there are reports of high mortality for cholangitis, although the mortality differs greatly depending on the year of the report and the severity of the disease. Even reports published in and after the 1980s indicate high mortality, ranging from 10% to 30% in the patients, with multiorgan failure as a major cause of death. Because many of the reports on acute cholecystitis and cholangitis use different standards, comparisons are difficult. Variations in treatment and risk factors influencing the mortality rates indicate the necessity for standardized diagnostic, treatment, and severity assessment criteria.

Systematic review and meta-analysis: does gall-bladder ejection fraction on cholecystokinin cholescintigraphy predict outcome after cholecystectomy in suspected functional biliary pain?

BACKGROUND

Patients with suspected functional biliary pain often undergo cholecystectomy if a decreased gall-bladder ejection fraction (GBEF <35%) is demonstrated by cholecystokinin cholescintigraphy. However, the validity of GBEF in predicting which patients will have symptomatic relief following cholecystectomy is unclear.

AIM

To determine whether patients with suspected functional biliary pain with decreased GBEF have a better symptomatic outcome after cholecystectomy than those with normal GBEF.

METHODS

Systematic review and meta-analysis of the published literature through MEDLINE and EMBASE databases.

RESULTS

We included nine studies with a total of 974 patients with suspected functional biliary pain; 362 patients underwent cholecystectomy. Most studies assessed outcome by direct patient interview. Mean ages across the studies ranged from 35 to 47 years; 78% of all patients were female. Mean duration of follow-up after surgery ranged from 1 to 2.5 years. After cholecystectomy, 94% of the patients with reduced GBEF had a positive outcome compared to 85% among those with normal GBEF. The pooled Mantel-Haenszel odds ratio for positive outcome was 1.37 (95% confidence interval 0.56-3.34), P=0.56.

CONCLUSION

These data do not support the use of GBEF to select patients with suspected functional biliary pain for cholecystectomy. Prospective randomized trials are required if this practice is to be evidence-based.

Endoscopic sonography in the diagnosis of gallbladder wall lesions in patients with gallstones

PURPOSE

The purpose of this study was to evaluate the diagnostic accuracy of endoscopic sonography (EUS) in the detection of gallbladder wall lesions in patients with and without gallstones.

METHODS

We retrospectively reviewed the medical records, sonograms, and sonographic reports of 62 patients who underwent cholecystectomy for gallbladder wall lesions evaluated by EUS. We assessed the accuracy of EUS in diagnosing gallbladder wall lesions in the presence or absence of gallstones and on the basis of the size and number of stones and the size of the gallbladder wall lesions. We also evaluated the effect of acoustic shadowing. The EUS results were compared with the histopathologic results.

RESULTS

EUS correctly diagnosed the gallbladder wall lesions in 17 (71%) of 24 patients with gallstones and in 34 (89%) of 38 patients without gallstones. The diagnostic accuracy of EUS was 86% in patients with gallbladder wall lesions smaller than 20 mm and 79% in patients with gallbladder wall lesions 20 mm or larger. The diagnostic accuracy was 75% in patients with gallstones smaller than 5 mm and 67% in patients with stones 5 mm or larger. The accuracy was 67% in patients with 1-5 stones and 83% in patients with 6 or more stones. None of these differences was statistically significant. Acoustic shadowing did not affect the diagnostic accuracy of EUS.

CONCLUSIONS

The diagnostic accuracy of EUS for gallbladder wall lesions is not affected by the presence of gallstones. However, better diagnostic criteria must be established based on larger studies, and technical refinements of the equipment are needed to increase the accuracy of EUS in the diagnosis of gallbladder wall lesions.

Gastrointestinal problems in the chronically critically ill patient

In summary, a variety of gastrointestinal processes may occur in the chronically critically ill patient population, usually as consequence of the primary systemic process. The clinical presentation is frequently nonclassic and there often is a substantial delay in diagnosis, resulting in increased morbidity and mortality.

Choledochal cyst associated with acute acalculous cholecystitis

A 7-year-old girl underwent laparotomy for suspected acute appendicitis. Instead, bile peritonitis with hydrops of gallbladder and normal appendix were noted. Dilatation of the CBD was observed, and choledochal cyst was documented by intraoperative cholangiography. Cholecystectomy and T-tube placement were performed. Postoperative follow-up by ultrasound lasted for 9 months. The CBD remained the same size without clinical manifestation.

Acute Acalculous Cholecystitis in Young Patients without Predisposing Factors

We report the atypical presentation of acute acalculous cholecystitis in four young, otherwise healthy patients. These cases emphasize the fact that the traditional concept of this disease as being associated with trauma, major surgery, or other pathology may no longer be true, and an important number of cases may appear de novo in patients without any predisposing factors.

Changing indications for laparoscopic cholecystectomy. Stones without symptoms and symptoms without stones

In less than a decade, laparoscopic methods have dramatically improved the safety and convenience of cholecystectomy. As a result, the number of cholecystectomies performed nationwide has increased significantly. Whether this increase is a reflection of any major change in operative indications is unclear; the actual answer may vary from community to community. Silent gallstones continue to represent a sometimes contentious therapeutic dilemma. Because their natural history is unlikely to have changed, the management guidelines previously established for open cholecystectomy continue to have relevance today. Thus, it can be agreed that the majority of patients with silent gallstones do not require a cholecystectomy. The changing risk-benefit ratio suggests that some liberalization of these guidelines may now be in order. Already a number of transplantation surgeons have begun to recommend pretransplant cholecystectomy for asymptomatic patients who are found to have gallstones during screening. Available evidence also appears to support the use of pre-emptive laparoscopic cholecystectomy for other indications such as in selected women of childbearing age, young children, and patients with very large gallstones. The problem of silent gallstones in diabetics continues to be more enigmatic, but some complicated diabetics are probably best managed with operation. Other patient groups who are at high risk of having adverse outcomes from expectant management will be more precisely identified by future research efforts. Laparoscopic cholecystectomy should also be helpful in patients with various forms of acalculous biliary disease. However, special caution is advisable in approaching chronic acalculous cholecystitis until more specific and reproducible diagnostic methods are further validated.

Importance of accurate preoperative diagnosis and role of advanced laparoscopic cholecystectomy in relieving chronic acalculous cholecystitis

Between April 1, 1989, and January 1, 1994, 38 patients with chronic acalculous cholecystitis underwent an advanced (3-puncture) laparoscopic cholecystectomy at our institution. The 30 women and 8 men had a mean age of 39 years (range, 23 to 65 years) and represented 4.5% of our overall gallbladder patient population. In each case, the disease produced typical biliary colic, but no gallstones were visualized on ultrasound examination; cholecystokinin-stimulated cholescintigraphy revealed a dysfunctional gallbladder, as evidenced by an ejection fraction of < or = 35% or nonvisualization or nonemptying of the organ. In all 38 cases, cholecystectomy resulted in the complete relief of symptoms. Although an increasing number of physicians are recommending this operation for acalculous gallbladder disease, it should not be performed on the basis of clinical history alone. Rather, objective criteria confirming the need for surgical intervention should be obtained by means of appropriate preoperative testing, including cholecystokinin-stimulated cholescintigraphy.

Acute Acalculous Cholecystitis

Acute acalculous cholecystitis (AAC) is a dangerous complication of medical and surgical illnesses, and it is most commonly encountered in the intensive care setting. Although uncommon, recent reports have indicated an increasing incidence. AAC occurs most often following major trauma or nonbiliary surgical procedures, but it may be seen in conjunction with avariety ofmedical illnessesaswell. Transfusion, narcotics, mechanical ventilation, total parented nutrition, and sepsis have been associated with AAC, but it is likely that ischemic injury to the gallbladder is the most important pathogenetic factor. Primary infection of the biliary tract is not an important factor in the development of AAC, except in the acquired immunodeficiency syndrome. The incidence of gangrene and perforation is high in AAC in contrast to acute calculous choleqstitis. The clinical presentation may be highly variable; thus, a high index of suspicion is required for diagnosis. Fever, leukocytosis, and right upper quadrant tenderness are the most common findings. Early ultrasonography is appropriate when AAC is suspected, although computed tomography and cholescintigraphy may be useful in selected patients. Delay in diagnosis longer than 48 hours is associated with a perforation rate of 40%. Urgent cholecystectomy is the preferred treatment, but percutaneous cholecystostomy is an acceptable alternative in patients unable to withstand surgery.

Chronic toxicity of dietary disodium arsenate heptahydrate to juvenile rainbow trout (Oncorhynchus mykiss)

Juvenile rainbow trout were fed semi-purified diets containing graded levels of disodium arsenate heptahydrate (DSA) for 12-24 weeks under standard laboratory conditions to define the maximum acceptable toxicant concentration (MATC) and to correlate signs of toxicity with diet and tissue arsenic concentrations. The MATC for DSA was between 13 and 33 micrograms As/g diet or 0.281-0.525 mg As/kg body weight/day. The most sensitive and reliable indicator of chronic dietary DSA toxicity in rainbow trout was chronic inflammation of the gallbladder wall. Chronic inflammatory changes in the sub-epithelial tissues of the gallbladder wall were evident in 71% of rainbow trout exposed to 33 micrograms As/g diet for 24 weeks, and 100% of rainbow trout exposed to 65 micrograms As/g diet for 24 weeks or 49 micrograms As/g diet for 12 weeks. No fish exposed to 13 micrograms As/g diet or less for up to 24 weeks showed any demonstrable gallbladder lesions or any other ill effect of arsenic exposure. Other signs of chronic dietary DSA toxicity to rainbow trout included decreased growth rate, mild to moderate anemia, and, at higher levels of exposure, active feed refusal leading to decreased feed consumption. Mild nephrocalcinosis was noted in one experiment where kidney arsenic residues exceeded 14 micrograms As/g tissue dry weight.