Liver Aspirates Research Articles

Liver aspirate from a Shar Pei dog

A 5-year-old, neutered male, Shar Pei dog was presented with weight loss, anorexia, lethargy, stranguria, and distal limb edema. Clinicopathologic abnormalities included anemia, an inflammatory leukogram, azotemia, icterus, urinary tract infection, and hepatomegaly with a markedly hypoechoic liver. Cytologic findings in a fine-needle aspirate of the liver included large amounts of amorphous, pink, extracellular matrix between hepatocytes. The amorphous material was congophilic using Congo red stain on a hepatic cytology specimen and green birefringent areas were observed under polarized light, confirming the presence of amyloid. The dog was euthanized and a necropsy was done. Histopathologic evaluation using H&E and Congo red staining confirmed amyloid deposits within the liver, kidneys, intestinal vessels, pancreas, and mesenteric ganglia. Immunohistochemical staining of liver and kidney sections using anti-AA amyloid and anti-P component antibodies confirmed the presence of AA amyloid. In this case, we demonstrated that Congo red staining and polarized light microscopy are a useful diagnostic technique in cytologic specimens of suitable thickness for confirming the presence of amyloid.

Comparative cytomorphology of skin, lymph node, liver and bone marrow in patients with lepromatous leprosy1

The aim of this study was to compare the cytological changes in skin, lymph nodes, liver and bone marrow in patients with lepromatous leprosy. Skin lesion, lymph node, liver and bone marrow aspirates were analysed. May-Grunwald-Giemsa (MGG) and Ziehl-Neelsen (Z-N) stains were employed. Comparative cytomorphology was studied. Twenty patients with lepromatous leprosy were studied. Lepra cells (LC) predominated in the skin aspirates of 12 patients with lepromatous leprosy (LL), lymphocytes accompanied LC in eight patients with borderline-lepromatous (BL) leprosy. Three patients of LL leprosy and two of BL leprosy in type 2 reaction additionally had numerous neutrophils. Two patterns of lymph node aspirates were seen: partial replacement with few LC in a reactive lymphoid background (10), complete replacement with either only LC or LC in a background of degenerating neutrophils (10), the latter a feature of type 2 reaction. Liver aspiration was performed in seven patients and of bone marrow in eight patients. Occasional LC were present in five liver-aspirated patients, steatosis and Kupffer cell hyperplasia in four patients, and myelopoiesis in two patients. Bone marrow smears invariably had occasional LC and a relative increase in mature plasma cells; sea-blue histiocytes were seen in six patients. Lepra cells predominated in skin and lymph node aspirates with complete replacement. In comparison, liver, bone marrow and lymph node aspirates with partial replacement were dominated by a preponderance of cells native to these organs with only few or occasional LC.

Cytological comparison of fine‐needle aspirates of liver and spleen of normal dogs and of dogs with cutaneous mast cell tumours and an ultrasonographically normal appearing liver and spleen

Staging of dogs with cutaneous mast cell tumours (MCTs) is an important diagnostic step. Aspiration of the liver and the spleen is often part of routine staging. This study cytologically compared mast cell numbers in fine-needle aspirates of liver and spleen of clinically normal unaffected dogs with those of dogs with cutaneous MCT and an ultrasonographically normal appearing liver and spleen. The unaffected dogs (n = 32) were selected from humane society dogs, and the affected dogs (n = 51) were selected from hospital cases. There were no statistically significant differences in each of the parameters evaluated for the liver aspirates. For splenic aspirates, affected dogs showed significantly more mast cells per cluster (P = 0.04) and more isolated mast cells per slide (P = 0.03) compared with unaffected dogs. However, no clinically important difference existed between the unaffected and affected dogs; thus, routine aspiration of an ultrasonographically normal appearing liver and spleen of dogs with cutaneous MCT does not appear to be a clinically useful staging tool.

Retrovirus‐Mediated Gene Transfer of Receptor Activator of Nuclear Factor‐κB‐Fc Prevents Bone Loss in Ovariectomized Mice

Postmenopausal osteoporosis is characterized by increased bone resorption due to estrogen deficiency. Receptor activator of nuclear factor-kappaB-Fc (RANK-Fc), a fusion protein that specifically blocks receptor activator of nuclear factor ligand binding to RANK, has been known to be efficient and well tolerated in animal models of osteoporosis. Here we show that cell-based gene therapy with RANK-Fc effectively prevented bone loss in ovariectomized (OVX) mice. Thirty-one young adult female C57Bl/6 mice were used, and repeated intraperitoneal injection of mesenchymal stem cells (MSCs) transduced with retrovirus was performed as follows: 1) Sham-operated mice (n = 8); 2) OVX mice treated with phosphate-buffered saline (OVX-PBS; n = 8); 3) OVX mice injected with MSCs transduced with control retrovirus (OVX-green fluorescent protein [GFP]; n = 7); and 4) OVX mice injected with MSCs transduced with RANK-Fc (OVX-RANK-Fc; n = 8). Cellular expression of RANK-Fc was confirmed by Western blot analysis of cell lysates and conditioned medium and also by enzyme-linked immunosorbent assay for the mice serum. Measurement of bone mineral density (BMD) by dual-energy x-ray absorptiometry (PIXImus) revealed that the OVX-RANK-Fc group gained significantly higher BMD than either the OVX-PBS group or OVX-GFP group after 8 weeks. The expression of GFP, which is coexpressed with RANK-Fc, was detected by polymerase chain reaction analysis of DNA isolated from femur and intra-abdominal fat, whereas no GFP signal was identified in liver, brain, heart, lung, or bone marrow aspirates. These suggest that expression of RANK-Fc by genetically modified MSCs may be a feasible option for the prevention of bone loss induced by ovariectomy.

Behandlung und Aufklärung bei unklarer Diagnose

An 82-year old female patient had an unclear gallbladder finding, and a laparoscopy was performed. The imaging techniques seemed to indicate gallbladder carcinoma infiltrating the liver. With the chosen method it was not possible to prove the actual existence of the cancer. The patient and her family were informed about the "benign" result and the patient was sent home. Three months later she died of gallbladder carcinoma, which was confirmed by liver aspiration during her last stay in hospital. The daughters were taken aback by the unexpected death of their mother. They declared that they would have spent the last three months differently, if they had been informed about the first suspected diagnosis and prognosis. Here we have a discussion about wasted chances. This article deals with the management of the fact that a diagnosed disease was ultimately fatal. It does not deal with the treatment of an advanced carcinoma of the gall-bladder with known lethal outcome. The approach can be twofold: a curative approach neglecting reality and patient communication on the one hand; a palliative approach with the goal of making the 'best' of the situation on the other. Regularly, after thorough clinical and technical examination we have evidence of cancer which we cannot actually prove by pathological confirmation. Very often these tumours are located in the pancreas and the biliary tract. When very old patients are concerned, decisions are even harder to take: how far are we to go with invasive examination methods and what will be the consequences after the existence of the cancer has been proven? What form should patient information take? In my opinion, all doctors are confronted with such situations almost daily.

Salmonellosis with liver abscess mimicking hepatocellular carcinoma in a diabetic and cirrhotic patient: a case report and review of the literature

Salmonellosis with liver abscess in a cirrhotic liver is extremely rare. We report the first case of Salmonellosis with septic shock and liver abscess in a diabetic and cirrhotic patient. The image studies of liver initially favored hepatocellular carcinoma. But no definite focus of sepsis was found. After close follow-up of the liver space-occupied lesion, ultrasound examination revealed the features of liver abscesses at space-occupied lesion later. Ultrasound-guided liver aspiration proved abscess. The clinical and radiological responses were good after antibiotics treatment.

Intra‐abdominal mass aspirate from a cat in heat

A 3-year-old intact female domestic shorthair cat was presented for the evaluation of a palpable intra-abdominal mass in the left caudal abdomen. The cat had a history of anorexia, depression and prolonged estrus over a period of about 1 month. Smears prepared from a fine needle aspirate of the mass revealed large round to oval cells arranged individually or in loose clusters surrounded by pink, fibrillar matrix material. Cytoplasm was basophilic, with many variably-sized vacuoles and variable numbers of small purple granules. The vacuoles within the cells were strongly positive with Oil-Red-O stain. The cytologic features were most suggestive of a neoplasm of epithelial cell origin or inadvertent aspiration of a fatty liver. At laparotomy, the mass was found to involve the left ovary. Histologically, the tumor consisted of dense sheets and nests of irregular polyhedral, pleomorphic cells with abundant, finely vesiculated cytoplasm. The tumor cells were separated into lobules by strands of connective tissue. Based on histologic evaluation, a diagnosis of ovarian luteoma was made. In this report, we document the cytologic and histologic features of an uncommon feline tumor, a luteoma, and address its possible misdiagnosis as hepatic lipidosis when using cytology alone to make a diagnosis.

Systemic Mycobacterium avium Infection in a Dog Diagnosed by Polymerase Chain Reaction Analysis of Buffy Coat

Dogs may be infected by Mycobacterium (M.) tuberculosis, M. bovis, and M. avium complex, and the clinical signs associated with each of these infections may be indistinguishable. Rapid speciation of the infecting organism is desirable because of the public health concerns associated with M. bovis and M. tuberculosis infections. A mycobacterial infection was suspected in the dog of this report based on acid-fast staining of organisms in macrophages obtained from liver aspirates and buffy-coat preparations. Polymerase chain reaction (PCR) analysis of a buffy-coat preparation identified M. avium.

Population-based study of the epidemiology of and the risk factors for pyogenic liver abscess

Pyogenic liver abscess (PLA) is relatively uncommon in North America but is associated with significant morbidity and mortality. Our objective was to characterize the incidence of, risk factors for, and outcomes of PLA in a nonselected population. Population-based surveillance was conducted in the Calgary Health Region (CHR) between April 1, 1999 and March 31, 2003. All adult CHR residents with PLA were identified, and charts were reviewed. Seventy-one CHR residents developed a PLA for an annual incidence of 2.3 per 100,000 population. There was an increasing incidence of PLA with advancing age. Men were at much higher risk of acquiring a PLA as compared to women (3.3 vs 1.3 per 100,000; relative risk [RR], 2.6; 95% confidence interval [CI], 1.5-4.6; P < .001), and this was observed across all age groups. A number of comorbid conditions were associated with significantly higher risk for developing a PLA including liver transplantation patients (RR, 444.8; 95% CI, 89.5-1356.0; P < .0001), diabetics (RR, 11.1; 95% CI, 6.3-19; P < .0001), and patients with a history of malignancy (RR, 13.3; 95% CI, 6.9-24.4; P < .0001). No other solid organ transplantation patient was at increased risk. All patients required admission to hospital (median length of stay, 16 days), and 7 (10%) patients died in hospital, corresponding to a mortality rate of 0.22 per 100,000 population. This study provides important data on the burden of PLA and identifies risk groups that might potentially benefit from preventive efforts.

Association between Liver Copper Concentration and Subclinical Hepatitis in Doberman Pinschers

The prevalence of subclinical hepatitis was investigated in a group of 106 randomly selected 3‐year‐old Doberman Pinschers. Histopathologic examination of liver samples from 65 dogs (52 dogs with high bile acids, alkaline phosphatase activity, or alanine aminotransferase activity or with copper granules in hepatocytes in a liver aspirate and 13 normal dogs) revealed subclinical hepatitis in 22 dogs (19 females and 3 males). Liver copper concentrations measured by instrumental neutron activation analysis was significantly higher (mean ± SD; 419 ± 414 μg/g dry matter) in dogs with hepatitis than those without liver disease (197 ± 113 μg/g; P= .0008). At 2.6 ± 0.6 years hepatitis persisted in 5 of 16 dogs available for examination. One dog with a high copper concentration but normal liver subsequently developed subclinical hepatitis after 3 years. During the follow‐up period, the average copper concentration of the 6 dogs with persistent subclinical hepatitis was 939 ± 299 μg/g and had continued to rise significantly (P= .02). The hepatitis in these dogs was associated with apoptotic hepatocytes and copper‐laden Kupffer cells in centrolobular regions. The results of this study suggest that there is a relationship among copper storage, hepatocellular damage, and hepatitis in Doberman Pinschers.

Diagnosis of a Hepatic Angiomyolipoma by Fine-Needle Aspiration: A Case Report

Hepatic angiomyolipomas (AML) diagnosed by fineneedle aspiration biopsy have only been reported sporadically. In this article, we present a case of hepatic angiomyolipoma diagnosed by fine-needle aspiration in a 55-year-old woman with an unexplained hepatic mass. The smears showed numerous arborizing capillary vessels transgressing sheets of cells with fibrillary cytoplasm and indistinct cytoplasmic border. Cell block sections showed sheets of epithelioid cells with eosinophilic granular cytoplasm or vacuolated, clear cytoplasm. Minimal amount of adipose tissue also was seen. Immunohistochemical stains revealed epithelioid tumor cells to be positive for HMB-45 and smooth muscle actin and negative for cytokeratin, supporting the diagnosis of angiomyolipoma. AML should be considered in the differential diagnosis when one encounters a tumor composed of epithelioid cells in a liver aspirate. Awareness of the rare occunence of AML in the liver and demonstration of a characteristic imlllunohistochemical profile are necessary for an accurate diagnosis. (The J Histotechnol 27:000, 2004)Submitted March 19, 2004; Accepted May 28, 2004

Diagnosis of a Hepatic Angiomyolipoma by Fine-Needle Aspiration: A Case Report

Hepatic angiomyolipomas (AML) diagnosed by fineneedle aspiration biopsy have only been reported sporadically. In this article, we present a case of hepatic angiomyolipoma diagnosed by fine-needle aspiration in a 55-year-old woman with an unexplained hepatic mass. The smears showed numerous arborizing capillary vessels transgressing sheets of cells with fibrillary cytoplasm and indistinct cytoplasmic border. Cell block sections showed sheets of epithelioid cells with eosinophilic granular cytoplasm or vacuolated, clear cytoplasm. Minimal amount of adipose tissue also was seen. Immunohistochemical stains revealed epithelioid tumor cells to be positive for HMB-45 and smooth muscle actin and negative for cytokeratin, supporting the diagnosis of angiomyolipoma. AML should be considered in the differential diagnosis when one encounters a tumor composed of epithelioid cells in a liver aspirate. Awareness of the rare occunence of AML in the liver and demonstration of a characteristic imlllunohistochemical profile are necessary for an accurate diagnosis. (The J Histotechnol 27:000, 2004)Submitted March 19, 2004; Accepted May 28, 2004

Distinguishing well-differentiated hepatocellular carcinoma from benign liver by the physical features of fine-needle aspirates

Distinguishing well-differentiated hepatocellular carcinoma (HCC) from benign hepatic lesions is challenging for pathologists in limited diagnostic material such as needle-core tissue biopsy and fine-needle aspiration (FNA) biopsy. The objective of this study is to test a hypothesis that the fortification of liver by reticulin along single cell plates should protect benign hepatic lesions from breakdown by the force of aspiration and smearing, whereas the decreased reticulin in well-differentiated HCC would result in finely granular FNA smear. The study involved FNA biopsies of 67 cases of well-differentiated HCC and 109 cases of benign hepatic lesions, including cirrhosis (22), liver cell adenoma (8), steatosis (7), focal nodular hyperplasia (6), liver with cholestasis (6), and unremarkable liver sampled from nodular hepatic lesions consistent with the regenerative nodules (60). A slide with the most sample from each case by gross inspection was mixed together. Two observers blinded to the diagnoses were asked to separate the slides into two groups based on smear characteristics by gross inspection. Fragments of rigid fine-needle cores was present in 109 out of 109 cases of benign hepatic lesions but absent in 61 out of 67 cases of well-differentiated HCC, which presented as finely granular smears. The difference is statistically significant. (P<0.001, df=1, χ2=149.3). Using the physical characteristic of liver aspirates as the screening test for malignancy, the sensitivity is 91%, specificity is 100%, positive predictive value is 100%, negative predictive value is 94.8%, and efficiency is 96.6%. In conclusion, the smear characteristics of liver samples in FNA biopsy correlate to their reticulin status on histology. This physical characteristic can be used as the first clue to distinguish malignant and benign liver aspirates prior to microscopic examination.

Liver aspirate cytology compared to liver biopsy

Liver aspirate cytology compared to liver biopsy

The Distribution of Sevoflurane in a Sevoflurane Induced Death

The distribution of sevoflurane (fluoromethyl 2,2,2,-trifluoro-1-(trifluoromethyl) ethyl ether) in blood, urine, liver, kidney, vitreous humor, and tracheal aspirate is presented from a subject with a sevoflurane induced death. Sevoflurane is a nonflammable general anesthetic administered by inhalation of vaporized liquid. Although general inhalation anesthetics have the potential to be fatal if not properly administered, the incidence of abuse is minute in comparison to other illicit drugs. Currently, there are no citations in the literature defining the body distribution of sevoflurane in a sevoflurane induced death. The decedent was found lying in a bed with an oxygen mask containing a gauze pad secured to his face. Three empty bottles and one partially full bottle of Ultane (sevoflurane) were found with the body in addition to two pill boxes containing a variety of prescription and non-prescription drugs. Serum, urine and gastric contents from the deceased were screened for numerous drugs and metabolites using a combination of thin layer chromatographic, colorimetric and immunoassay techniques. Analysis of biological specimens from the deceased revealed the presence of: amphetamine, caffeine, pseudoephedrine, nicotine, nicotine metabolite, and valproic acid. Sevoflurane concentrations were determined by headspace gas chromatography with flame ionization detection and revealed concentrations of 26.2 microg/mL in the blood, 105 microg/mL in the urine, 31.9 microg/mL in the tracheal aspirate, 86.7 microg/mL in the vitreous humor, 30.8 mg/kg in the liver, and 12.8 mg/kg in the kidney. The decedent had pathologies consistent with respiratory suppression including pulmonary atelectasis, pulmonary edema, and neck vein distention. The official cause of death was respiratory suppression by sevoflurane and the manner of death was unclear.

Association between Liver Copper Concentration and Subclinical Hepatitis in Doberman Pinschers

The prevalence of subclinical hepatitis was investigated in a group of 106 randomly selected 3-year-old Doberman Pinschers. Histopathologic examination of liver samples from 65 dogs (52 dogs with high bile acids, alkaline phosphatase activity, or alanine aminotransferase activity or with copper granules in hepatocytes in a liver aspirate and 13 normal dogs) revealed subclinical hepatitis in 22 dogs (19 females and 3 males). Liver copper concentrations measured by instrumental neutron activation analysis was significantly higher (mean +/- SD; 419 +/- 414 microg/g dry matter) in dogs with hepatitis than those without liver disease (197 +/- 113 microg/g; P = .0008). At 2.6 +/- 0.6 years hepatitis persisted in 5 of 16 dogs available for examination. One dog with a high copper concentration but normal liver subsequently developed subclinical hepatitis after 3 years. During the follow-up period, the average copper concentration of the 6 dogs with persistent subclinical hepatitis was 939 +/- 299 microg/g and had continued to rise significantly (P = .02). The hepatitis in these dogs was associated with apoptotic hepatocytes and copper-laden Kupffer cells in centrolobular regions. The results of this study suggest that there is a relationship among copper storage, hepatocellular damage, and hepatitis in Doberman Pinschers.

Hepatoblastoma in a 15-Month-Old Male: Cytomorphology, Electron Microscopy, and Differential Diagnosis

The authors describe a case of hepatoblastoma in a 15-month-old male and discuss the differential diagnosis and electron microscopic features of small round cell tumors. The patient was found to have an enlarged liver and was admitted to the hospital for further investigation. Fine-needle aspiration of the liver revealed small. uniform cells with increased nuclear/cytoplasmic ratio and focal rosette formation. A diagnosis of small blue cell neoplasm favoring hepatoblastoma was made, but neuroblastoma could not be ruled out. Electron microscopic analysis performed on the liver aspirate showed features of hepatic differentiation as well as absence of neuroblastic differentiation. The diagnosis of hepatoblastoma was made. Serum alpha-fetoprotein level of 33,250 mg/L confirmed the diagnosis. Liver biopsy performed subsequently showed tumor cells arranged in nests, acini, and trabeculae with mitotic figures. Electron microscopy showed the same findings as described above. The patient underwent chemotherapy for 4 months and subsequently a partial liver resection was performed. This case illustrates the important role of electron microscopy in evaluating small round cell tumors in children.

Hepatic abscess after liver transplantation: 1990-2000.

Infections following solid-organ transplants are a major cause of morbidity and mortality. Few studies have reported the complications of hepatic abscesses. This investigation consisted of a retrospective chart review of all solid-organ transplant recipients from 1990 to 2000. Criteria for diagnosis included parenchymal hepatic lesions, positive cultures from liver aspirates or blood cultures, or both, and a compatible clinical presentation. Of 2,175 recipients of all organ transplants (heart, lung, kidney, liver, pancreas), we identified 12 patients who had experienced 14 episodes of hepatic abscess, all in liver transplant recipients. Median time from transplant to hepatic abscess was 386 days (range 25-4,198). The most common predisposing factor was hepatic artery thrombosis (HAT), which occurred in eight patients, and was diagnosed at an average of 249 days (range 33-3,215) after transplantation. Clinical presentation of hepatic abscess was similar to that described in non-immunosuppressed patients. All but one patient showed hypoalbuminemia (<3.5 g/dL); those with HAT also had significantly elevated lactate dehydrogenase. Liver aspirates grew gram-positive aerobic bacteria (50% of isolates), gram-negative aerobic bacteria (30%), and anaerobes and yeasts (10% each). Patients received an average of 6 weeks of intravenous antibiotic therapy. Catheter drainage was successful in 70% of cases; and five patients required retransplantation. Altogether, five of the patients died, yielding a mortality rate of 42%. Hepatic abscess, a rare complication after liver transplantation, was frequently associated with hepatic artery thrombosis. Mortality was higher than in patients who had not undergone transplantation. Prolonged antibiotic therapy, drainage, and even retransplantation may be required to improve the outcome in these patients.

Hepatoblastoma in a 15-Month-Old Male: Cytomorphology, Electron Microscopy, and Differential Diagnosis

The authors describe a case of hepatoblastoma in a 15-month-old male and discuss the differential diagnosis and electron microscopic features of small round cell tumors. The patient was found to have an enlarged liver and was admitted to the hospital for further investigation. Fine-needle aspiration of the liver revealed small, uniform cells with increased nuclear/cytoplasmic ratio and focal rosette formation. A diagnosis of small blue cell neoplasm favoring hepatoblastoma was made, but neuroblastoma could not be ruled out. Electron microscopic analysis performed on the liver aspirate showed features of hepatic differentiation as well as absence of neuroblastic differentiation. The diagnosis of hepatoblastoma was made. Serum alpha-fetoprotein level of 33,250 mg/L confirmed the diagnosis. Liver biopsy performed subsequently showed tumor cells arranged in nests, acini, and trabeculae with mitotic figures. Electron microscopy showed the same findings as described above. The patient underwent chemotherapy for 4 months and subsequently a partial liver resection was performed. This case illustrates the important role of electron microscopy in evaluating small round cell tumors in children.

A global emerging disease of Klebsiella pneumoniae liver abscess: is serotype K1 an important factor for complicated endophthalmitis?

Over the past two decades in Taiwan, pyogenic liver abscess has usually been caused by a single microorganism, Klebsiella pneumoniae, and is frequently associated with the serious complication of endophthalmitis, especially in diabetic patients. However, the relationship between the clinical presentation and bacterial factors remains unclear. The aim of this study was to investigate the clinical features of patients and the serotype and ribotype of K pneumoniae liver abscess. From July 1991 to June 1998, a total of 134 cases of K pneumoniae liver abscess with 248 K pneumoniae isolates from the same patients were collected from two large medical centres in northern Taiwan. Clinical data were collected from medical records. Serotyping and ribotyping were performed using the countercurrent immunoelectrophoresis method and automated Riboprinter. Serotyping revealed that the most common serotypes were K1 (63.4%) and K2 (14.2%). K1 isolates occurred at a significantly higher frequency (p<0.01) than all other serotypes. Among 134 patients, 105 (78.4%) had suffered from diabetes mellitus for 3-15 years. Fourteen patients (10.4%) had metastatic infection to the eye causing septic endophthalmitis. Liver aspirates, and blood and vitreous pus cultures yielded the same serotype of K pneumoniae in all patients. Among patients with septic endophthalmitis, 92.3% (13/14) were diabetic, and 85.7% (12/14) of the isolates belonged to serotype K1. For molecular typing, different degrees of genetic polymorphism among isolates with the same K1 serotype suggested no particular prevalence of any one strain in K pneumoniae liver abscess. K pneumoniae serotype K1 was significantly associated with liver abscess and the complication of endophthalmitis, especially in diabetic patients. Physicians should request an immediate report of serotyping and susceptibility test results simultaneously if a diagnosis of pyogenic liver abscess has been made so that early and appropriate management for possible complications will not be delayed. The use of ceftriaxone because of its higher concentration in the aqueous humor is suggested to decrease the chance of septic endophthalmitis.