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Colloid keratosis. Morphologic characterization of a nonspecific reaction pattern of squamous epithelium.

Colloid keratosis is characterized by homogeneous eosinophilic masses of variable size and number within the upper layers of squamous epithelia, including epidermis. It has been observed as the characteristic feature of many onychoses and inflammatory conditions of oral epithelium, and as an incidental finding in neoplastic and nonneoplastic lesions in the skin and respiratory tract. Its nature remains obscure, but knowledge at present suggests that it may represent a disorder of an early phase of keratinization. Current evidence supports the hypothesis that colloid keratosis represents a nonspecific cellular reaction pattern of squamous epithelium.

Adult↗

Acute cerebral effects of isotonic crystalloid and colloid solutions following cryogenic brain injury in the rabbit.

Despite the numerous studies examining the relative merits of crystalloids versus colloids for expansion of intravascular volume, little attention has been directed to the cerebral effects of these solutions. In particular, the effect of changes in plasma oncotic pressure on brain water content are poorly understood. The authors recently examined the acute effects of changes in plasma osmolality and colloid oncotic pressure in normal animals, and found that a 65% reduction in oncotic pressure had no detectable effect on brain water content or intracranial pressure. In an effort to extend these studies to a more clinically relevant situation, the authors have now compared the acute effects of 0.9% saline, 6% hetastarch, and 5% albumin on regional cerebral water content and intracranial pressure in an animal model of brain injury produced by focal cortical freezing. Under general anesthesia and following the production of the cryogenic brain lesion, rabbits underwent a 45-min period of isovolemic hemodilution to a hematocrit of 20-25% with one of the three selected fluids. The saline group required approximately twice as much fluid (207 +/- 17 ml) to maintain a stable mean arterial pressure and central venous pressure as did the hetastarch (105 +/- 14 ml) or albumin (103 +/- 29 ml) groups. As intended, the oncotic pressure decreased by a mean of 9.6 +/- 2.4 mmHg in the saline group, while remaining stable in the hetastarch and albumin groups. There were no significant changes in osmolality in any group during the hemodilution period.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumins↗

Colloid determination of fibrin network permeability.

The effects of polymers, dextran and polyvinylpyrolidone (PVP) and of albumin on the permeability of thrombin-induced fibrin networks developed in plasma were examined. Both PVP and dextran increased the network permeability and turbidity and increased the fibrin fibre thickness. The effect was molecular weight dependent. Derivation of the dimensionless permeability (permeability/fibre radius2) indicated that the increase in network permeability was mainly from altered arrangement of fibres and not from increased fibre thickness. The effects of albumin on network structure were similar to those of the polymers. Scanning electron microscopy of networks developed in plasma under the influence of dextran and poloxamer 188 showed fibres with increased thickness and a coarse nodular appearance. There was an increased tendency for fibres to be aggregated into clumps. It is suggested that during polymerization fibrin fibres and fibrin polymerization intermediaries behave as colloidal particles. Attractive forces between the particles are generated by soluble macromolecules such as plasma proteins or polymers. Attractive forces increase the thickness of fibrin fibres and induce a more permeable arrangement of the fibres in the network. The most likely colloidal mechanism is depletion flocculation. This would account for (1) the molecular weight dependence and concentration dependence of the effects of macromolecules, (2) the effects of macromolecules which do not bind to fibrin, (3) the effects of the surfactant poloxamer 188. Depletion flocculation may be a significant mechanism for biological regulation of fibrin network permeability by non-specific macromolecules such as soluble proteins or fibrin intermediaries.

Albumins↗

The effects of perioperatively administered crystalloids and colloids on concentrations of molecular markers of activated coagulation and fibrinolysis.

To explore whether intravenous administration of routinely used crystalloid or colloid solutions differently affects the coagulation system, we investigated orthopaedic patients. Since crystalloid solutions might cause hypercoagulability, we here present our results on molecular markers of coagulation and fibrinolysis. Patients undergoing knee replacement surgery randomly received isovolemic amounts of lactated Ringer's solution, 6% hydroxyethyl starch 200/0.5 or 4% modified gelatine. Arterial blood samples for determination of specific molecular markers of activated coagulation (thrombin/antithrombin complex, D-dimer, prothrombin fragment F1 + 2), fibrinolysis (plasmin/alpha 2-antiplasmin complex, tissue plasminogen activator, plasminogen activator inhibitor-1), and concentrations of coagulation factor XIII were obtained at baseline, before tourniquet release, at the end of surgery and 2 h after operation. During the observation period, thrombin/antithrombin complex increased from 4.8 to 54.7 microg/l, D-dimer increased from 0.3 to 6.0 mg/ml, prothrombin fragment F1 + 2 increased from 1.7 to 5.9 nmol/l, tissue plasminogen activator decreased from 7.3 to 6.7 ng/ml, plasminogen activator inhibitor-1 increased from 68.4 to 71.0 ng/ml, plasmin/alpha 2-antiplasmin complex increased from 281.5 to 884 microg/l and factor XIII decreased from 89.0 to 58.5%. All parameters changed significantly but without any detectable difference in the response profile between the groups receiving different intravenous fluids. During knee replacement surgery a pronounced activation of the coagulation/fibrinolytic system was observed, regardless of whether patients received crystalloid or colloid fluids. Thus, these results cannot confirm the hypothesis that crystalloid fluids per se cause hypercoagulability in vivo.

Aged↗

A prospective randomized trial evaluating colloid versus crystalloid resuscitation in the treatment of the vascular leak syndrome associated with interleukin-2 therapy.

Interleukin-2 (IL-2)-based therapy induces a vascular leak syndrome (VLS), manifested by hypotension, tachycardia, and oliguria, as is also seen with septic shock. The optimal method for treating such VLS is not known. A prospective randomized trial was undertaken to compare crystalloid and colloid fluid resuscitation for patients receiving bolus IL-2-based therapy for metastatic cancer. All patients received maintenance crystalloid fluid administration and were randomized to receive crystalloid (0.9% normal saline) or colloid (5% human serum albumin) fluid boluses to maintain acceptable vital signs and urine output. Patients refractory to fluid boluses were given dopamine for oliguria and/or phenylephrine for hypotension. Of 107 patients who completed one cycle of therapy on study, 76 completed a full treatment course (two cycles) on study. The total number of saline and albumin fluid boluses given were 9.5 +/- 0.9 versus 7.7 +/- 0.7 (p = 0.36, n = 107) for the first cycle and 19.2 +/- 1.8 versus 16.1 +/- 1.6 (p = 0.33, n = 76) for a complete course, respectively. Although patients receiving saline boluses had significantly more oliguria during a course of therapy, weight gain, number of IL-2 doses, tachycardia, hypotension, vasopressor use, hospital stay, and clinical response rates did not significantly differ between arms. Changes in hematocrit, hemoglobin, protein, albumin, blood urea nitrogen (BUN), and creatinine were analyzed, and patients receiving crystalloid showed greater decreases in albumin (p < 0.0001) and total protein (p < 0.05) as expected. A 40-fold greater cost associated with albumin suggested that crystalloid resuscitation be used to treat the VLS associated with IL-2 therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Right-sided spleen with partial situs inversus of the abdominal viscera: visualization of the spleen by dynamic and static 99mTc-sulfur colloid imaging and 51Cr-labeled red blood cell sequestration imaging.

In a patient with right-sided stomach and malrotation of the small bowel and cecum visualized by gastrointestinal x-ray studies using barium, a right-sided spleen was demonstrated by 99mTc-sulfur colloid and 51Cr-labeled red blood cell imaging. The sulfur colloid study also demonstrated that the liver was in its usual right upper quadrant location.

Adult↗

Hepatic imaging: a comparison of Tc-99m-sulfur colloid and PIPIDA in the detection of defects.

A prospective investigation comparing Tc-99m-PIPIDA with Tc-99m-sulfur colloid in the detection of defects of the liver was carried out in 30 volunteers. By acquiring images of 1 million counts from 5-10 minutes postinjection, high quality hepatic images could be obtained with PIPIDA. Separate interpretations by three nuclear physicians yielded similar results between paired PIPIDA and sulfur colloid studies (KAV = 0.95 +/- .09, P less than 0.001). Early multiview imaging of the liver in the course of hepatobiliary evaluation with PIPIDA may yield valuable information relative to the presence of lesions.

Humans↗

Scintigraphic detection of pulmonary hemorrhage using Tc-99m-sulfur colloid.

Pulmonary hemorrhage, whether in the form of hemoptysis or bleeding into the pleural space, may be a life threatening problem. While fiberoptic bronchoscopy and selective bronchial and intercostal angiography are the major diagnostic modalities, these techniques are not without risks. Two patients are described-one with massive hemoptysis from a bronchogenic carcinoma; another with pleural bleeding from a torn intercostal artery-in whom Tc-99m-sulfur colloid scintigraphy accurately located the source of hemorrhage. We conclude that Tc-99m-sulfur colloid scintigraphy may be a helpful noninvasive method to increase the sensitivity and specificity of fiberoptic bronchoscopy and bronchial angiography in patients with massive pulmonary bleeding.

Adult↗

Absence of hepatic uptake of Tc-99m sulfur colloid in an infant with Coxsackie B2 viral infection.

After the intravenous administration of Tc-99m sulfur colloid, there was found homogeneous lung, renal, and splenic uptake with absence of uptake by the liver and bone marrow of a nine-day-old female infant. More than 20 other doses were dispensed from the same Tc-99m sulfur colloid preparation with the expected biodistribution. A necropsy done two days later showed diffuse hepatic hemorrhagic necrosis without evidence of intravascular fibrin deposition in the lungs or kidneys. The underlying cause of the infant's disease was a Coxsackie B2 viral infection, based upon positive postmortem viral cultures of kidney and liver tissues and characteristic histopathologic lesions of the central nervous system and viscera. The altered biodistribution presumably reflected marked impairment of Kupffer cell function and an apparent increase in pulmonary macrophages.

Coxsackievirus Infections↗

Discordant Tc-99m sulfur colloid and In-113m chloride blood pool images in patients with acute amebic liver abscess.

Using combined Tc-99m sulfur colloid and In-113m chloride eluate imaging, studies from 32 patients with proven amebic liver abscess were analyzed. The results revealed good perfusion of the amebic lesion in three, poor perfusion in 11, and absent perfusion in 18. These results appear to depend on abscess size and age. Images with In-113m seem to be better than those with Tc-99m sulfur colloid in depicting amebic liver abscess during antiamebic therapy. Overall, the In-113m images provide more precise information concerning abscess size and shape.

Acute Disease↗

Simultaneous demonstration of pleural effusion and ascites by technetium-99m sulfur colloid liver-spleen scintigraphy.

Scintigraphic evidence of ascites has been observed in Tc-99m sulfur colloid studies of the liver and spleen, in Tc-99m HIDA hepatobiliary scans, in Ga-67 citrate scans, and in Tc-99m phosphonate bone images. Pleural effusion has been demonstrated in Tc-99m phosphonate bone scintigraphy. The case of a 48-year-old man whose Tc-99m sulfur colloid liver-spleen scintigram simultaneously demonstrated a right pleural effusion and ascites is presented.

Ascites↗

Pelvic lesion simulated by asymmetric marrow uptake following umbilical artery injection of technetium-99m sulfur colloid.

There is avid first-pass extraction of Tc-99m sulfur colloid by bone marrow. This factor must be considered when injection of the isotope is made via an unusual route. Tc-99m sulfur colloid was injected via an umbilical artery catheter into an infant's left iliac artery, causing marked marrow uptake in the left pelvis. The paucity of uptake on the right side of the pelvis simulated metastatic replacement of the marrow. A repeat study done via the jugular vein demonstrated no abnormalities of pelvic marrow uptake.

Bone Marrow↗

Failure of technetium-99m sulfur colloid uptake by the femoral head. Aseptic necrosis or normal variation?

The hips of 79 asymptomatic patients having Tc-99m sulfur colloid liver/spleen scans were imaged. Patients were not studied if they had a disease associated with nonvisualization of the femoral heads. The first group consisted of 47 consecutive patients who were imaged in a neutral position. Eighteen right and 18 (38.3%) left hips showed no activity. The second group consisted of 32 consecutive patients who were imaged in an internally rotated position. Seven (21.9%) right and nine (28.1%) left hips showed no activity. This study concludes that failure of uptake of Tc-99m sulfur colloid by the femoral head is seen in a sufficiently large group of patients to limit its use in diagnosing aseptic necrosis.

Femur Head↗

Quantitative evaluation of postembolized splenic tissue using technetium-99m sulfur colloid.

Tc-99m sulfur colloid scans were used to quantitate the percent of residual splenic tissue after partial splenic embolization (PSE) performed for the treatment of hypersplenism in 17 renal transplant patients. A liver-spleen phantom was designed which simulated the human liver and spleen configuration to evaluate the technique. This phantom contained a solution of tc-99m sulfur colloid, which allowed precise quantities of the spleen phantom volume to be displaced using lucite pseudo-emboli. After each lucite embolus, computer images of the spleen phantom were collected and analyzed in the same manner used for the transplant patients. Correlation of the actual volume displaced or embolized with the computer estimated values was 0.996 (P less than 0.001). This technique was superior to both CT and MRI, which were more difficult to perform and less precise in measuring a decrease in postinfarction functioning splenic tissue.

Embolization, Therapeutic↗

Importance of Tc-99m sulfur colloid liver-spleen scans performed before indium-111 labeled leukocyte imaging for localization of abdominal infection.

INTRODUCTION: The localization of intraabdominal abscesses is a difficult imaging problem in nuclear medicine, especially when the location of the abscess is in the area of the liver and spleen. The need for performing Tc-99m sulfur colloid liver-spleen scans before injecting indium-111 leukocytes for improved lesion detection and characterization versus performing In-111 leukocyte scans alone has been questioned in the literature MATERIALS AND METHODS: We present 3 patients with intraabdominal abscesses in the liver-spleen area, in which liver-spleen scans were performed before In-111 leukocyte scans. The findings of all were correlated with computed tomography and interventional procedures. RESULTS: In all patients, the Tc-99m liver-spleen scan helped for accurate recognition of the location of the abscess, correlated with computed tomography findings, and were helpful for intervention and exclusion of the other sources of infection. CONCLUSION: Data from these 3 patients reinforces the need for Tc-99m sulfur colloid liver-spleen scans before performing In-111 WBC scans for better localization and interventional treatment of intraabdominal abscesses.

Abdominal Abscess↗