[Potential use of bone marrow scintigraphy in suspected prosthetic hip infection evaluated with 99mTc-HMPAO-leukocytes]

AIM

To evaluate the usefulness of (99m)Tc-Sulphur colloid when combined with leukocyte scintigraphy in suspected prosthetic hip infection, comparing the results with information from (99m)Tc-HMPAO-leukocyte scintigraphy alone.

MATERIALS AND METHODS

Seventy patients (42 women, 28 men; mean age 68 +/- 13 years) with painful hip prostheses and suspicion of infection were evaluated prospectively. All patients had bone scintigraphy, (99m)Tc-HMPAO-labelled white blood cell scintigraphy and (99m)Tc-Sulphur colloid bone marrow scintigraphy. ESR and CRP levels were measured in all patients. The final diagnosis was made with microbiological findings or by clinical follow up of at least 12 months.

RESULTS

Infections were diagnosed in 12 of the 70 patients (3 coagulase-negative Staphylococcus, 2 Staphylococcus aureus, 2 Staphylococcus epidermidis, 2 enterococcus and 3 polymicrobial agents). ESR and CRP values were higher in patients with infection than in patients without infection (51.8 +/- 29.4 vs. 25.4 +/- 16.4 and 2.8 +/- 2.2 vs. 1.1 +/- 1.3, respectively; p < 0.05). Bone scintigraphy did not show a characteristic pattern to differentiate infection from aseptic loosening. The pool phase of the bone scintigraphy was positive in only 3/12 patients with infection (25 %). Sensitivity and specificity of the leukocyte scintigraphy was 83 % and 57 %, respectively. When the results of the bone marrow scintigraphy were added, these values increased to 92 % and 98 %, respectively.

CONCLUSION

Performing bone marrow scintigraphy significantly improves results when compared with leukocyte scintigraphy alone in the diagnosis of infected hip prostheses. Bone scintigraphy did not help to differentiate aseptic loosening from infection in this series.

Utilidad de la gammagrafía con plaquetas marcadas con 111In-oxina en el manejo del síndrome febril en pacientes en diálisis portadores de injerto renal no funcionante

AIM

To evaluate the usefulness of 111In-oxine-labelled platelet scan in the therapeutic management of prolonged febrile syndrome in dialysis patients with a non-functional renal allograft.

MATERIAL AND METHODS

One hundred and fifty-eight patients (94 men, 64 women; mean age 44 +/- 9 years) were studied. Duration of fever was 42 days (range 7-112). A total of 68 % of the patients (107/158) were on low doses of corticosteroids (<10 mg/day). Platelet scans were performed 48 hours after reinjection of 111In-ixone-labelled platelets. A platelet uptake index (PUI) was calculated by dividing the cpm/pixel in the allograft by the cpm/pixel in a mirror background. A PUI > or = 1.5 was considered as threshold for immunological fever. The final diagnosis of immunological fever was established when it disappeared after transplantectomy, embolization or high doses of corticosteroid therapy. Fever of non-immunological origin was established when it disappeared after antibiotic therapy.

RESULTS

In 102/158 patients the fever was considered of immunological origin. In 56/158 patients the fever was considered of non immunological origin. Sensitivity and the specificity of the platelet scan was 80 % and 100 %, respectively. All those patients considered as having fever of immunological origin who had PUI <1.5 had been using corticosteroids during platelet scan.

CONCLUSION

111In-labelled platelet scintigraphy is a useful technique in the therapeutic management of prolonged febrile syndrome in dialysis patients with non-functional renal allograft. The use of corticosteroids can reduce the sensitivity of 111In- labelled platelet scan.

111Indium labelled leukocyte scintigraphy in the detection of acute prostatitis

Although prostatitis is a common problem the diagnosis is still controversial despite the availability of a wide variety of diagnostic tools. In fact, there is still no accurate method of localizing the infected tissue. The aims of the present study were to assess whether 111In labelled leukocytes (ILLs) accumulated in the infected tissue of acute prostatitis and if such uptake responded to treatment. We prospectively studied 10 adult male patients who had community acquired prostatitis and compared them with six male patients who had urinary tract infections but without prostatitis. An initial urinary culture and two blood cultures were carried out for each patient. All patients were followed up for 8 weeks after therapy was completed. Pre- and post-treatment scintigraphies were performed. Before treatment, all patients with prostatitis showed uptake of ILLs in the prostate area. After the patients had completed treatment with antibiotics, the scintigraphy results showed no uptake in the prostate area in 9/10 patients. The remaining patient showed a marked decrease in the uptake of ILLs. None of the six patients with urinary tract infection showed ILL uptake in the prostate region. It is suggested that ILLs could be useful for detecting acute prostatitis, especially in clinically ambiguous patients with urological infections. Furthermore, scintigraphy with 111In labelled leukocytes could help to determine the most appropriate course of therapy.

[Fast method of labelling leukocytes with 99mTc HM PAO]

OBJECTIVE

To modify the method of labelling leukocytes with 99mTc HM-PAO by centrifuging 15 minutes at low gravity (g) instead of sedimentation at a variable time (30-90 minutes) to obtain leukocytic rich plasma (LRP).

METHODS

The g number recovering the greatest number of leukocytes was determined. The cellular composition of LRP obtained by centrifugation and sedimentation was analyzed. Lastly, labelling results in two groups of patients (p) were compared: one group of 118 p using the traditional sedimentation method (SM) and another of 124 p using the proposed centrifugation alternative (CM).

RESULTS

Centrifugation at 5xg produced the greatest recovery of leukocytes (93.1 5.1%). No significant difference was observed in leukocyte recovery in LRP obtained either by centrifugation or by sedimentation. However, red blood cell contamination was greater in centrifugation (12.8 4.9 x 108) than in sedimentation (7.7 3.5 x 108) (p < 0.0001). The comparison of the SM and the CM gave the following results:The number of leukocytes recovered in both methods was similar (73.9 15.1% vs 76.5 12.7%) with approximately the same platelet contamination (8.0 6.2 vs 8.4 6.5%). The number of red blood cell contaminants per leukocyte was 3.0 1.0 for the MS and 5.1 2.6 for the MC (p < 0.001). Labelling yield (LY) was somewhat higher for the CM (57.8 11.9%) than for the SM (50.8 12.6%) as a result of greater red blood cell contamination and superior radiochemical purity of the 99mTc HM-PAO used in the labelling by CM (90,9 5,9%) with regard to the SM (87.9 9.5%). No difference was observed in the scintigraphic images obtained with either of the methods, given the scarce uptake of the radiopharmaceutical by the red blood cells (3-7%) in comparison with the leukocyte uptake (70-90%).

CONCLUSION

The proposed MC considerably reduces the labelling time of leukocytes with 99mTc HM-PAO without affecting the quality of scintigraphic images and represents an important labelling alternative of great interest to the Radiopharmacy Units of Nuclear Medicine Services.

Transfusion of incompatible RBCs to a patient with alloanti-Kp(b)

BACKGROUND

The finding of an antibody that reacts against a high-incidence blood group antigen always constitutes a complex transfusion problem because of the difficulty in finding compatible units. When the transfusion of incompatible RBCs is imperative, it would be of great interest to have access to techniques facilitating the prediction of the transfusion outcome.

STUDY DESIGN AND METHODS

The case of a patient with alloanti-Kp(b) who required RBC transfusions is reported. The functional activity of this antibody was assessed by both the chemiluminescence test (CLT) and the survival of 51Cr-labeled RBCS:

RESULTS

The CLT showed an opsonic index of 0.8 with Kp(b)-positive RBCs (normal values up to 1.6) in pretransfusion studies. During an elective surgical procedure, the patient required the transfusion of one incompatible unit of RBCs, which did not produce hemolysis. Two weeks after this incompatible transfusion, the opsonic index had risen to 11. Results of the 51Cr in vivo study, also performed at that time, indicated 24.3 percent survival of Kp(b)-positive RBCs at 60 minutes and 2.0 percent at 24 hours.

CONCLUSION

Results of the CLT correlated with the in vivo transfusion outcome and later with the 51Cr survival study.

Acute effects of the anti-inflammatory cyclooxygenase-2 selective inhibitor, flosulide, on renal plasma flow and glomerular filtration rate in rats

Nephrotoxicity of nonsteroidal anti-inflammatory drugs is associated with other risk factors (volume-depletion) and may be secondary to functional changes mediated by the inhibition of renal cyclooxygenases. Acute anti-inflammatory doses of flosulide and indomethacin were determined on carrageenan paw edema and its effects on renal plasma flow (RPF) and glomerular filtration rate (GFR) were studied in normovolemic and hypovolemic rats. In normovolemic rats, flosulide increased RPF and GFR (25 mg/kg) and indomethacin (5-10 mg/kg) was without effect. Volume-depleted rats were obtained by oral furosemide (32 mg/kg), urinary eicosanoids were determined. After furosemide, plasma volume, RPF and GFR and PGE2 decreased. Treatment of hypovolemic rats with flosulide (5-25 mg/kg) or indomethacin 10 mg/kg reduced RPF and GFR. Flosulide at 5 mg/kg reduced 6-keto-PGF1alpha whereas at 25 mg/kg and after indomethacin at 10 mg/kg a fall in 6-keto-PGF1alpha and TXB2 appeared. Our data suggest that acute COX-2 selective inhibition may alter renal function.

123Iodine-labelled anti-VCAM-1 antibody scintigraphy in the assessment of experimental colitis

OBJECTIVES

To evaluate the usefulness of 123I-labelled anti-vascular cell adhesion molecule-1 (VCAM-1) monoclonal antibody (MAb) scintigraphy in the assessment of colonic inflammatory damage.

DESIGN

Colitis was induced by intracolonic administration of 30 mg trinitrobenzenesulphonic acid in 0.5 ml of 50% (v/v) ethanol. Rats injected with vehicle served as controls. Animals were studied at day 7 after induction of colitis.

METHODS

Scintigraphy was performed in control and trinitrobenzenesulphonic acid-induced colitic rats 2, 4 and 24 h after intravenous administration of 123I-anti-VCAM-1 MAb. Scintigraphic uptake was quantified in selected areas on scintigraphs. Animals were killed, tissue 123I radioactivity accumulation was measured, and accumulation of anti-VCAM-1 MAb in each organ was calculated. 99mTc-hexamethyl propylene amine oxime-labelled leucocyte scintigraphy was performed in additional groups of animals for comparison.

RESULTS

Colonic tracer uptake was visible in scans of colitic, but not control animals. Quantification of scintigraphic uptake in the colon was significantly higher in colitic rats than in control animals (P< 0.0001). The specificity of the increase was demonstrated by lack of 123I-labelled non-binding MAb uptake in the colon, and by displacement of 123I-anti-VCAM-1 MAb colonic uptake by pre-treatment with unlabelled MAb. Accumulation of anti-VCAM-1 MAb in the colon of colitic rats was eightfold higher than in control animals. Strong correlations were found between quantification of scintigraphic uptake, anti-VCAM-1 MAb accumulation, histological damage and myeloperoxidase activity in the colon.

CONCLUSION

123I-labelled anti-VCAM-1 MAb scintigraphy allows an accurate evaluation of colonic inflammatory damage in trinitrobenzenesulphonic acid-induced colitis, suggesting a potential role for this imaging technique in the assessment of human IBD.

Simultaneous technetium-99 MAG(3), iodine-131-orthoiodohippurate and iodine-125 iothalamate clearance and biodistribution after bolus injection in rats

A bolus injection multiple blood sampling method was developed for the simultaneous measurement of blood and plasma clearance of three radiopharmaceuticals in rats. Technetium-99m mercaptoacetyltriglycine ([(99m)Tc]MAG(3)) and iodine-131-orthoiodohippurate ([(131)I]OIH) were used as makers of effective renal blood flow (ERBF), and iodine-125 iothalamate ([(125)I]IOT) was used as a marker of glomerular filtration rate (GFR). These methods can be easily performed in rats without arterial catheterization. Tissue biodistribution was studied in four groups of rats subjected to the following: group A, renal pedicle isolation (sham-operated); group B, ligature of one kidney pedicle; group C, ligature of both renal pedicles; and group D, ligature of both kidney pedicles and the bile duct. Renal clearance of [(99m)Tc]MAG(3) was greater than [(131)I]OIH and both agents were cleared faster than ([(125)I]-IOT). Either of the two markers of ERBF may be used in experimental studies, but it should be borne in mind that these are relative measurements of kidney performance. [(99m)Tc]MAG(3) and [(125)I]-IOT showed bile excretion in healthy rats, so they cannot completely fulfill the requirements for use as markers of ERBF. When renal function was impaired experimentally, [(99m)Tc]MAG(3) and [(125)I]-IOT were excreted in bile and [(131)I]OIH was secreted in the intestine. Thus, while the markers of ERBF and GFR may be reliable under normal physiological conditions, they may give progressively more erroneous values as renal function deteriorates.

Serum cystatin C as a new marker for noninvasive estimation of glomerular filtration rate and as a marker for early renal impairment

Cystatin C is a nonglycosylated basic protein produced at a constant rate by all investigated nucleated cells. It is freely filtered by the renal glomeruli and primarily catabolized in the tubuli (not secreted or reabsorbed as an intact molecule). Because serum cystatin C concentration is independent of age, sex, and muscle mass, it has been postulated to be an improved marker of glomerular filtration rate (GFR) compared with serum creatinine level. We compared serum cystatin C level with other markers of GFR, such as serum creatinine level and creatinine clearance, and analyzed their variations based on iothalamate labeled with iodine 125 ((125)I-iothalamate) clearance ((125)I-ICl), used as the gold standard for GFR. The concentrations of the two different markers of GFR in patients with impaired renal function were classified according to (125)I-ICl. Twenty individuals with normal renal function ((125)I-ICl, 128 +/- 23 mL/min/1.73 m(2)) were used as the control group. Serum cystatin C level showed a greater sensitivity (93.4%) than serum creatinine level (86.8%). Also, serum cystatin C showed the greatest proportion of increased values in patients with impaired renal function (100%) compared with serum creatinine level (92.15%). Serum cystatin C levels started to increase to greater than normal values when GFR was 88 mL/min/1.73 m(2), whereas serum creatinine level began to increase when GFR was 75 mL/min/1.73 m(2). These data suggest that measurement of serum cystatin C may be useful to estimate GFR, especially to detect mild reductions in GFR, and therefore may be important in the detection of early renal insufficiency in a variety of renal diseases for which early treatment is critical.

Indium-111 labelled platelet scintigraphy can predict the immunological origin of fever in patients on dialysis carrying a non-functioning renal allograft

The purpose of this study was to evaluate the usefulness of labelled platelet scintigraphy in the differential diagnosis of a prolonged febrile syndrome (PFS) in patients on dialysis carrying a non-functioning renal allograft. We prospectively performed an indium-111 mercaptopyridine-labelled platelet scan on 91 patients (54 men, 37 women; mean age 39.6+/-12 years). The mean duration of PFS was 35 days (range 7-122). Forty-six of the 91 patients underwent steroid therapy (2-10 mg/day). Platelet labelling was carried out following Thakur's method. Platelet scans were performed 48 h after reinjection of labelled platelets. The platelet uptake index (PUI) was calculated by dividing the cpm/pixel in the allograft ROI by cpm/pixel in a mirror background ROI. The final diagnosis of PFS was established depending on the outcome after treatment. In 61/91 patients the fever had an immunological origin because it disappeared after graft embolisation or transplantectomy. In 30/91 patients the PFS disappeared after antibiotic therapy (non-immunological origin). The PUI in patients with immunological PFS was 1.80+/-0.7, while in patients with non-immunological PFS it was 1.12+/-0.1 (P<0.05). When a PUI of > or =1.5 was considered as the threshold to establish PFS of immunological origin, the sensitivity of platelet scan was 76%, the specificity 100%, and the negative and positive predictive values 69% and 100%, respectively. In patients classified with immunological PFS who underwent steroid therapy, the PUI was significantly lower than in patients without steroids (P<0.05). These results suggest that 111In-labelled platelet scintigraphy can accurately predict an immunological PFS in patients on dialysis carrying a non-functioning renal allograft. Therapy with steroids could reduce the sensitivity of 111In-labelled platelet scintigraphy in detecting immunological PFS.

Migration pathways of hypodermically injected technetium-99m in dogs

Hypodermic injection of technetium-99m (99mTc-pertechnetate) at points of low electrical resistance give rise to rapid, longitudinal, and progressive diffusion of the radioactive tracer. We assessed the effect of cutaneous incisions that did not intersect the migration trajectory of 99mTc-pertechnetate and the re-establishment of pathways after the suture of incisions that intersected the migration trajectory. Linear and rapid migration of 99mTc-pertechnetate was not altered or prevented by incisions that did not intersect the migration pathway. Different patterns of 99mTc-pertechnetate spread were found when incisions intersected the radioactive pathways until restoration of the normal migration pathway observed in undamaged skin occurred. In all experiments in which migration of 99mTc-pertechnetate was observed, lavage of surgical wounds was followed by disappearance of the 99mTc-pertechnetate migration observed around the suture. Linear migration of the tracer was not observed when the incision was left uncovered, filled with petroleum jelly, or with a solid silicone sheet, but it was seen when non-sutured incisions were filled with transonic or silicone gel or covered with a solid silicone sheet parallel to the cutaneous plane. These data show that after a cutaneous incision that intersected the diffusion trajectory of the radioactive tracer, linear migration of 99mTc-pertechnetate hypodermically injected at points of low electrical resistance was restored before healing of the cutaneous incision and was independent of incisions made on the skin not overlying the radioactive pathway. A mechanism similar to that of capillary electrophoresis is suggested to explain the hypodermic diffusion of inert particles through specific and constant linear pathways.

Effect of nasogastric tube size on gastroesophageal reflux and microaspiration in intubated patients

BACKGROUND

Little evidence exists to support the theory that small-bore nasogastric tubes prevent gastroesophageal reflux and microaspiration in intubated patients.

OBJECTIVE

To determine whether gastroesophageal reflux and microaspiration in intubated patients can be reduced by the use of a small-bore nasogastric tube.

DESIGN

Randomized, two-period crossover trial.

SETTING

Respiratory intensive care unit of a university hospital.

PATIENTS

17 patients intubated for more than 72 hours.

INTERVENTIONS

Radioactive technetium colloid was instilled in each patient's stomach. Patients were studied with two nasogastric tubes (one tube with a 6.0-mm external bore and one tube with a 2.85-mm external bore) in randomized order; measurements of radioactive counts with the alternate size of nasogastric tube were repeated 72 hours after original measurements were taken. Sequential samples of serum, gastric juice, and pharyngeal and tracheal secretions were obtained.

MEASUREMENTS

Comparison of the time course of radioactive counting in all samples (obtained during the use of each nasogastric tube size in each patient).

RESULTS

The mean radioactive count of pharyngeal aspirates (P = 0.004) was greater than the baseline count at all time points, as was the cumulative radioactive count of pharyngeal aspirates 17 hours after the first dose of technetium colloid was administered (P = 0.001); however, the count of tracheal aspirates was never greater than the count at baseline. No differences were found between tube types when the time course and cumulative counts of pharyngeal and tracheal samples were compared.

CONCLUSION

Small-bore nasogastric tubes in intubated patients do not reduce gastroesophageal reflux or microaspiration.

Experiences in setting up the first centralized radiopharmacy in Spain

The centralized radiopharmacy set up in Spain by the Cetir Medical Group allows optimal use of radiopharmaceuticals and complies with laws (Directive 89/343/EEC and Royal Decree 479/1993/Spain) governing their use. More than 220,000 individual patient doses have been supplied since the unit was established in November 1995. In this paper, we describe the infrastructure of the centralized radiopharmacy, including the operations and procedures involved, and how we believe we have achieved our original objectives.

[Plasma homocysteine levels in patients with ischemic cerebral infarction]

BACKGROUND

Moderate hyperhomocysteinemia is an independent risk factor for stroke. The relationship between homocysteinemia and stroke and its related factors are unknown in Spain.

PATIENTS AND METHODS

We determined plasma homocysteine concentrations in 80 stroke patients and in 48 control subjects without vascular risk factors. Folate, vitamin B12 and creatinine concentrations were also measured in stroke patients.

RESULTS

Total plasma homocysteine concentrations were higher in stroke patients compared to controls (11.2 [SD 3.2] mumol/l versus 8.1 [2.6] mumol/l; p < 0.001). Hyperhomocysteinemia was present in 20% of patients and in 2.2% of controls (odds ratio [OR] = 5.75; 95% CI = 1.24-53.4; p < 0.01). Homocysteine values were related to vitamin B12 (r = 0.28; p < 0.05) and creatinine concentrations (r = 0.24; p < 0.05). Multiple regression analysis showed that about 15% of the variation in plasma homocysteine concentrations could be predicted by the values of vitamin B12 (p < 0.001) and creatinine (p < 0.05). Homocysteine values were unrelated to age, sex, folate concentrations, atherosclerotic subtype or to the presence of vascular risk factors.

CONCLUSIONS

Moderate hyperhomocysteinemia was present in about 20% of stroke patients in our series. Homocysteine plasma level was not related with other stroke risk factors or with the atherosclerotic subtype of stroke, but it was partially related with the renal function parameters and the serum levels of vitamin B12.

Effect of therapeutic paracentesis on plasma volume and transvascular escape rate of albumin in patients with cirrhosis

BACKGROUND/AIMS

Circulatory abnormalities with activation of vasoconstrictor systems after large-volume paracentesis are generally considered secondary to an increased extravasation of fluid from the intravascular compartment to the extravascular space with subsequent reduction in plasma volume. To test this hypothesis, plasma volume, the transvascular escape rate of albumin, the absolute escape rate of albumin and the activity of vasoconstrictor systems were measured in 25 cirrhotic patients with ascites in baseline conditions and 2 days after total paracentesis with plasma volume expansion.

METHODS

Plasma volume and the transvascular escape rate of albumin, the fraction of albumin passing from the intravascular to the extravascular space per unit of time, were assessed through the plasma disappearance curve of radioiodinated human albumin. The absolute escape rate of albumin, the total flux of albumin from intravascular to extravascular space per unit of time, was also calculated.

RESULTS

Eight of the 25 patients (32%) developed marked activation of vasoconstrictor systems after paracentesis. In these patients, plasma renin activity and plasma norepinephrine concentration increased from 6.6+/-2 to 23.4+/-11 ng x ml(-1) x h(-1) and 776+/-229 to 989+/-258 pg/ml, respectively (p<0.05). No significant changes in these parameters were found in the remaining 17 patients. The activation of vasoconstrictor systems occurred in the absence of changes in plasma volume (3456+/-276 vs 3476+/-264 ml, NS), transvascular escape rate of albumin (10.4+/-1 vs 10.9+/-2%/h, NS) and absolute escape rate of albumin (9.9+/-1.9 vs 10.5+/-0.7 g/h, NS).

CONCLUSIONS

These results do not support a contraction of plasma volume as the mechanism responsible for activation of vasoconstrictor systems after paracentesis. Rather, the activation of vasoconstrictor systems in the absence of changes in plasma volume suggests that paracentesis accentuates the impairment of "effective" blood volume present in cirrhotic patients with ascites.

Circulatory effects of graded diversion of portal blood flow to the systemic circulation in rats: role of nitric oxide

Total portal-systemic shunting in normal animals is associated with splanchnic and systemic vasodilation, suggesting that vasodilation in cirrhosis may be facilitated by spontaneous shunts promoted by portal hypertension. However, the mechanism of this vasodilation is unknown. The aim is to study the acute effects of the graded diversion of portal blood flow to the systemic circulation in normal and portal hypertensive rats. Portal and systemic hemodynamics were measured in normal and portal hypertensive rats before and during graded portacaval diversion of portal blood flow, in basal conditions, and after nitric oxide inhibition. In portal hypertensive rats, graded portal flow diversion caused a rate-related decrease in portal pressure (from 15.3 +/- 0.6 to 11.2 +/- 0.7 mm hg at 6 mL x min(-1), P < .001) and a redistribution of portal-collateral blood flow from the spontaneous portal-systemic collaterals to the portacaval circuit, without changing total portal-systemic shunting. Graded portal diversion caused an immediate systemic vasodilation, with reduced peripheral resistance. This vasodilatory response was more pronounced in normal than in portal hypertensive rats (increase in cardiac index 23.6% +/- 2.8% vs. 8.5% +/- 4.9%, P < .02, fall in peripheral resistance -24.5% +/- 3.4% vs. -16.5% +/- 2.6%, P = .08), and was totally prevented by nitric oxide inhibition. The graded diversion of portal blood flow caused a flow-rate-related reduction in portal pressure and blood flow through spontaneous portal-systemic collaterals in portal hypertensive rats, and caused a nitric-oxide dependent systemic vasodilatory response, which was greater in normal than in portal hypertensive rats. These results suggest that portal-systemic shunting per se may contribute to the vasodilatation in portal hypertension.

Estimation of 99Tcm-MAG3 clearance using a single blood sample obtained over a continuous time interval

Simplified methods based on a single blood sample have been proposed to estimate the clearance of 131I-hippuran (HIP) and 99Tcm-mercaptoacetyltriglycine (MAG). The blood sample is usually drawn at that time which yields a minimum error between the estimated clearance and that obtained by the standard nine-sample method. In this paper, we establish the regression equations to obtain the HIP and MAG clearances using one sample withdrawn during a fixed time interval. As HIP has long been the agent of choice, we have also established regression equations to estimate the clearance of HIP using one sample after MAG administration. Our results suggest that it is possible to obtain plasma samples 30-50 min post-injection which result in an error of the estimate only slightly higher than the minimum.

Salbutamol reduces pulmonary neutrophil sequestration of platelet-activating factor in humans

To investigate whether salbutamol inhibits platelet-activating factor (PAF)-induced neutrophil sequestration in the lungs, we studied eight nonatopic, nonsmoking, healthy subjects (six men; aged 27.0 +/- 1.5 (SE) yr) with PAF-induced bronchial response. Prior to PAF challenge (24 micrograms), they inhaled either salbutamol (300 micrograms) or placebo in a randomized, double-blind, crossover manner two weeks apart. Respiratory system resistance (Rrs), arterial blood gases, and neutrophil counts were measured 4, 8, 12 and 30 min after PAF. Neutrophil kinetics in the lungs were assessed by tracking autologous 99mTc-erythrocytes and 111in-neutrophils. Compared with salbutamol, arterial blood neutrophil counts fell (p < 0.04) maximally at 4 min after PAF, followed by a mild rebound neutrophilia, whereas Rrs increased (p < 0.01) and Pao2 decreased (p < 0.05) at 4 min only. The intrapulmonary activity of 111in-neutrophils after pretreatment with placebo was higher compared with salbutamol (1.98 +/- 0.15 versus 1.33 +/- 0.23 cps/mCi/pixel) (p < 0.01) although both their initial sequestration (first-pass) and subsequent washout were not significantly different. Inhaled salbutamol blocks pulmonary neutrophil sequestration and lung function abnormalities following PAF challenge in humans.

Scintigraphic evaluation of the severity of inflammation of the joints with 99TCm-HIG in rheumatoid arthritis

A prospective study was carried out to determine the usefulness of 99TCm-human immunoglobulin G (HIG) scintigraphy in the assessment of the severity of joint inflammation. Twenty-four patients with rheumatoid arthritis were studied. The presence or absence of pain and/or swelling was evaluated in 34 joints and a clinical index taking into account the surface area of each joint was calculated. We measured the following biological markers of inflammation activity: erythrocyte sedimentation rate, C-reactive protein, haemoglobin, platelet count, serum levels of IL-6, TNF-alpha and soluble receptors of IL-2. Scintigraphic was performed 4 h after the injection of 740 MBq 99Tcm-HIG. The scans were evaluated by visual and quantitative analysis and the scores in each joint were weighted for joint size. Pathological uptake of the radiopharmaceutical was noted in 46% (24/52) of joints evaluated as painful, 89% (146/164) of swollen joints and 94% (78/83) of both painful and swollen joints. Both the visual and the quantitative scintigraphic indices correlated significantly with the clinical index, the number of painful joints, the number of swollen joints and several biological markers of inflammation. A very high correlation was also found between the visual and the quantitative scintigraphic indices (r = 0.91, P < 0.0001). In conclusion, 99Tcm-HIG scintigraphy is an objective test to detect synovitis and to assess the severity of inflammation. A careful visual analysis of scans is good enough for routine evaluations and computer quantitative analysis should be used when more accurate intra-individual variation is required.

Semirecumbent position protects from pulmonary aspiration but not completely from gastroesophageal reflux in mechanically ventilated patients

The aim of this study was to evaluate the effect of two body positions (supine and semirecumbency) on the dynamics of gastroesophageal reflux (GER) in 15 patients requiring mechanical ventilation and having a nasogastric tube in place. Samples of gastric contents, pharyngeal and bronchial secretions, and blood were obtained at baseline and every hour during a period of 5 h after nasogastric tube isotopic instillation of 37 megabecquerels of Tc99m. Radioactivity counting (RAc) was performed using a gamma counter with correction for decay. Irrespective of the body position, all patients showed at 3, 4, and 5 h after the isotope instillation a significant increase in RAc of the oropharyngeal contents (p < 0.05, each), indicating GER. Although RAc values in the pharynx were higher in supine from 1 through 4 h (p < 0.05), at the end of the study (5 h) the values did not differ between each position. Likewise, the slopes of the regression lines of sequential oropharyngeal RAc values were not different between each position (0.39 +/- 0.09 versus 0.45 +/- 0.11, respectively). In contrast, RAc values in bronchial secretions were higher at 5 h in the supine position compared with baseline (p < 0.05) and to semirecumbency (p < 0.01). These results strongly support that GER in mechanically ventilated patients with a nasogastric tube is a feature occurring irrespective of body position. Semirecumbent position does not protect completely from GER and subsequently from oropharyngeal colonization from gastric origin.

Age-dependent enzymuria, proteinuria and changes in renal blood flow and glomerular filtration rate in rats

The time course of urinary excretion of two enzymatic indicators of renal damage, N-acetyl-beta-D-glucosaminidase (NAG) and alanine aminopeptidase (AAP) was measured in female Wistar rats at different ages. NAG and AAP are localized at different sites of the nephron and are released into the urine when kidney damage occurs. Total protein flow, urinary volume and creatinine flow were also determined. In a parallel experiment, the effect of aging on renal blood flow (RBF) and glomerular filtration rate (GFR) was examined in young (1.5-month) adult (3-month) and elderly (20-month) female rats. Clearance following a single injection of [131I]o-iodohippurate (hippuran, OIH) was used for the measurement of effective RBF and as an index of tubular cell function. [125I]Iothalamate (IOT) clearance was used to measure GFR. With advancing age, an increase in NAG and AAP urinary flow appeared. The increases in protein excretion were greater than and previous to those of enzyme excretion. It is shown that absolute RBF and GFR (ml/min) in old rats are greater than in young or adult animals. When absolute RBF or GFR was divided by kidney weight (ml/min/g) no clearance changes appeared in any age group studied; only when clearance was expressed in relation to body weight (ml/min/100 g), a decrease in RBF and GFR was evidenced. This indicates that the rate of increase of both RBF and GFR with age is similar to that of kidney weight and lower than that of body weight. The present findings indicate that urinary markers of renal injury increase with age, whereas GFR and RBF only decrease when expressed as clearance related to body weight.

Evidence against a role for inducible nitric oxide synthase in the hyperdynamic circulation of portal-hypertensive rats

BACKGROUND/AIMS

Excessive nitric oxide biosynthesis caused by expression of inducible NO synthase has been implicated in the hyperdynamic circulation of portal hypertension. The aim of the study was to investigate whether inducible NO synthase is expressed in portal hypertension an accounts for the hyperdynamic circulation.

METHODS

In study 1, NO synthase activities were measured by the conversion of L-arginine to citrulline in tissues from portal-hypertensive, cirrhotic, and sham-operated rats and from normal rats pretreated with endotoxin and after long-term administration of dexamethasone, which inhibits the expression of inducible NO synthase. In study 2, systemic and splanchnic hemodynamics (radiolabeled microspheres) and gastric blood flow (hydrogen gas clearance and reflectance spectrophotometry) were measured in portal-hypertensive rats after long-term administration of dexamethasone (0.25 mg.kg-1.day-1) or vehicle.

RESULTS

In study 1, constitutive and inducible NO synthase activities in portal-hypertensive or cirrhotic rats were similar to those observed in sham-operated rats. The significant increase in the inducible activity observed after endotoxin injection was prevented when rats received long-term treatment with dexamethasone. In study 2, cardiac index, portal-pressure, portal venous inflow, and gastric blood flow were similar in dexamethasone-or vehicle-treated portal-hypertensive rats.

CONCLUSIONS

These results to not support a role for an increased expression of the inducible NO synthase in the hyperdynamic circulation of portal hypertension.

Procedure for red blood cell labelling with 99mTc-HMPAO. Methodology and quality control

We present here results on the labelling of red blood cells with 99mTc-HMPAO as an alternative method to the usual in vitro technique. Anticoagulant agents, the labelling medium with plasma, and the lapse of time between 99mTc-HMPAO preparation and labelling are the main factors which affect the efficiency of the procedure. A 93.9 +/- 2.3% labelling yield was obtained with freshly prepared 99mTc-HMPAO. In vitro (tracer elution of 4.3 +/- 1.2% at 60 mins) and in vivo (percentage of plasma activity at 60 mins, 7.8 +/- 2.8%) stability of the label, as well as image quality, qualify 99mTc-HMPAO labelled red blood cells as a suitable agent for clinical use.

Effects of low-sodium diet and spironolactone on portal pressure in patients with compensated cirrhosis

The aim of this study was to investigate the hemodynamic effects of spironolactone associated with a low-sodium diet (n = 14) or a low-sodium diet alone (n = 9) in patients with compensated cirrhosis and portal hypertension. Spironolactone significantly reduced the plasma volume. This effect was associated with a significant reduction in the hepatic venous pressure gradient, from 17.6 +/- 3.6 mm Hg to 15.3 +/- 3.5 mm Hg (-13% +/- 13%; p < 0.01). Azygos blood flow (-20% +/- 20%), cardiac output (-16.2% +/- 10.5%) and mean arterial pressure (-9% +/- 9%) also decreased significantly. However, there were no significant changes in hepatic blood flow. Patients receiving low-sodium diet alone experienced a mild but significant reduction in hepatic venous pressure gradient (-6.3% +/- 6%) and in mean arterial pressure (-4% +/- 5%). There were no significant changes in cardiac output and in hepatic or azygos blood flows. This study indicates that low-sodium diet plus administration of spironolactone reduces portal pressure and azygos blood flow in patients with compensated cirrhosis. Low-sodium diet alone only produces mild effects that are likely to be clinically irrelevant.

Effects of chronic normovolemic anemia on gastric microcirculation and ethanol-induced gastric damage in rats

The effects of chronic normovolemic anemia on gastric microcirculation and gastric mucosal susceptibility to ethanol-induced gastric damage were investigated in anesthetized rats. Blood exchange by a plasma expander during four consecutive days rendered the animals anemic with a 34% decrease in the baseline hematocrit but without affecting blood volume. Chronic anemia induced a decrease in whole blood viscosity, an increase in gastric mucosal blood flow measured by hydrogen gas clearance, a decrease in gastric vascular resistance, and a decrease in gastric hemoglobin content without changes in the gastric oxygen content, the latter two parameters being measured by reflectance spectrophotometry. Gastric mucosal blood flow was lowered by intragastric administration of 100% ethanol in both anemic and control rats, but the final blood flow was significantly higher in anemic than in control animals. Macroscopic gastric damage induced by ethanol administration was significantly lower in anemic than in control rats. We conclude that chronic normovolemic anemia increases gastric mucosal blood flow and leads a protecting mechanism against gastric mucosal damage induced by absolute ethanol.

[Initial iron deposits in idiopathic myelofibrosis. Analysis of 20 patients]

PURPOSE

To analyse the status of iron deposits at diagnosis in patients with idiopathic myelofibrosis (IM).

PATIENTS AND METHODS

The study included twenty consecutive patients with IM. Haemoglobin, MCV, serum iron and serum ferritin were determined in each case. Perls stain was used to evaluate iron deposits in bone marrow samples attained by aspiration or biopsy. An attempt was made to correlate the semiquantitative estimation of bone marrow iron with the peripheral blood values connected with iron deposits.

RESULTS

Anaemia was present in 15 patients, but in most cases MCV and serum iron were normal. Iron deposits in bone marrow aspirate could be evaluated only in one patient as in the remainders no material was obtained. The semiquantitative estimation of iron in bone marrow biopsy samples showed diminished or absent deposits in 15 cases (75%). In contrast, none of the patients had decreased serum ferritin levels. No correlation was found between bone marrow iron and the peripheral blood values related to iron deposits.

CONCLUSION

Most IM patients have decreased bone marrow iron deposits at diagnosis. However, as in chronic myelogenous leukaemia and in essential thrombocytopenia, such finding does not mean a true iron deficiency status.

Failure of frusemide to increase production of prostaglandin E2 in human nasal mucosa in vivo

BACKGROUND

It has been suggested that inhaled frusemide protects subjects with asthma against bronchoconstriction by enhancing the synthesis of prostaglandin E2 (PGE2). To evaluate this hypothesis the effect of frusemide on PGE2 production from nasal mucosa was studied.

METHODS

Two main arachidonic acid metabolites produced by epithelial cells, PGE2 and 15-hydroxy 5,8,11,13-eicosatetraenoic acid (15-HETE), were measured by radioimmunoassay in nasal secretions obtained by nasal lavages with saline. Eleven healthy volunteers were randomly assigned to two study days, one week apart, in a double blind crossover study. Nasal instillation with three increasing doses of frusemide (5, 10, and 20 mg) or placebo was carried out at intervals of 15 minutes. Nasal lavages were performed immediately before nasal instillations and 15, 30, and 60 minutes after the last instillation.

RESULTS

Baseline concentrations of 15-HETE were at least six times higher than PGE2. No differences between frusemide and placebo were detected either on PGE2 or 15-HETE release.

CONCLUSIONS

The findings do not support the hypothesis that the antiasthmatic effect of frusemide may be due to increased synthesis of PGE2 or release in the respiratory mucosa.

Detection and quantitative analysis of joint activity inflammation with 99Tcm-polyclonal human immunoglobulin G

99Tcm-polyclonal human immunoglobulin G (HIG) scintigraphy was used to detect active joint inflammation and to obtain ratios of joint uptake in noninvolved and inflammatory joints. Imaging was performed at 4 and 24 h in 16 patients with rheumatoid arthritis (RA) and 16 with degenerative joint disease (control group). All joints (total of 1344) were scored for pain, swelling and visual analysis of uptake in both scans. Joint to background (J:B) ratios were also calculated. Clinical and visual scores correlated in both scans (r = 0.7, P < 0.01). In RA patients, 246 joints were clinically involved. Visual analysis of scans detected 213 (87%) of them at 4 h and 196 (80%) at 24 h. Joints with no pain or swelling showed significantly higher J:B ratios than the control group and lower ratios than joints clinically involved. In the control group, statistically significant differences in J:B ratios between the various joints were found, so it was necessary to establish a normal range for every joint. J:B ratios were significantly higher at 4 h than at 24 h in both groups of patients. 99Tcm-HIG scintigraphy allows detection and measurement of joint inflammation. Scans performed at 4 h are preferable to scans at 24 h. Quantitative analysis can measure more objectively the degree of activity and could be useful in the management of these patients.

Effects of somatostatin on renal function in cirrhosis

To investigate the renal effects of somatostatin in cirrhosis, renal function and plasma and urinary levels of endogenous neurohumoral vasoactive substances were measured in conditions of intravenous water overload (20 mL/kg body wt with 5% glucose) before and during the intravenous infusion of somatostatin (250-500 micrograms/h) in 6 cirrhotic patients without ascites and 17 nonazotemic cirrhotic patients with ascites. Somatostatin induced a significant reduction of renal plasma flow, glomerular filtration rate, and free water clearance in both groups of patients. In patients with ascites, somatostatin also reduced urinary sodium excretion. Changes in renal function were significantly more marked in patients with ascites than in those without ascites and occurred in the absence of changes in mean arterial pressure and plasma levels of renin, aldosterone, norepinephrine, antidiuretic hormone, and atrial natriuretic peptide. Somatostatin induced a significant reduction in the plasma concentration of glucagon and urinary excretion of prostaglandin E2 that was not related to changes in renal function. These findings indicate that somatostatin administration induces renal vasoconstriction and impairs glomerular filtration rate, free water clearance, and sodium excretion in cirrhosis by a mechanism unrelated to systemic hemodynamics and endogenous neurohumoral vasoactive systems.

[Ferrokinetic studies in the initial evaluation of idiopathic myelofibrosis: results in 18 patients]

BACKGROUND

Since there is no effective treatment for idiopathic myelofibrosis (IM) the determination of possible factors which are involved in the appearance of anemia in this disease may be important from a practical point of view.

METHODS

The results of the initial ferrokinetic study analyzed in 18 patients with IM included plasma clearance (T1/2) and globular incorporation (U max) of 59Fe in addition to the uptake of 59Fe in the sacrum, spleen and liver in 16 patients. The clinical-hematologic and histologic data of the different groups of patients identified according to the results of the study were compared.

RESULTS

Three ferrokinetic patterns were observed: 1) normal or increased erythropoiesis (8 patient), 2) inefficient erythropoiesis (7 patients), and 3) aplastic pattern (3 patients). The only difference observed between the three groups was the existence of lower levels of Hb and reticulocytes in the subjects with aplastic type pattern. In contrast, although there was an inverse correlation between the medullar and extramedullar uptake of iron (p = 0.018) no relation was observed between the latter and the size of the spleen or liver.

CONCLUSIONS

The results obtained in this study indicate that IM behaves heterogeneously from a ferrokinetic point of view.

Body water compartments in patients with obstructive jaundice

To elucidate the pathogenesis of renal dysfunction associated with obstructive jaundice, body water compartments were measured using a multi-isotope dilution technique in ten patients with biliary tract obstruction and in ten control subjects matched for age, sex, weight, height and body surface area. Expressed as a fraction of body-weight, total body water was reduced in jaundiced patients (41.8 versus 46.2 per cent, P less than 0.02). Extracellular water volume was also reduced in patients with jaundice (20.3 versus 24.3 per cent, P less than 0.003) owing to a reduction of the interstitial space (16.1 versus 19.5 per cent, P less than 0.004) and, to a lesser degree, of the plasma volume (4.2 versus 4.8 per cent, P = 0.1). There was a close correlation in jaundiced patients between plasma volume and the creatinine clearance rate (r2 = 0.56, P less than 0.02) and between plasma volume and extracellular volume (r2 = 0.77, P less than 0.0001). Extracellular volume in such patients also correlated with the percentage weight loss (r2 = 0.42, P = 0.04). Obstructive jaundice is associated with a contracted extracellular water compartment, although extracellular water, as a percentage of body-weight, increased in proportion to the body-weight lost. Reduction of the interstitial volume and a marginally reduced plasma volume may be determinant factors in the pathogenesis of the renal and haemodynamic disturbances observed in patients with biliary tract obstruction.

Effects of long-term rifampicin administration in primary biliary cirrhosis

The effects of rifampicin treatment (10 mg.kg-1.day-1) on pruritus and cholestasis were evaluated in 16 patients with primary biliary cirrhosis and pruritus followed up for 2-24 months. Assessment of pruritus severity, liver tests, aminopyrine breath test, and bile acids was done at 2 weeks and every 3 months after the beginning of the study. Two patients (12.5%) were withdrawn after 2 months of treatment because they had hepatitis caused by rifampicin. Four patients were withdrawn after 4 months because of liver transplantation (3 cases) and the development of leg edema associated with administration of rifampicin. The remaining 10 patients received therapy for 14.4 +/- 0.7 months and did not experience side effects. Pruritus improved in all patients and disappeared in 11 patients (79%) after 3 months of treatment. Moreover, all patients followed up for more than 1 year were free of pruritus. The alkaline phosphatase level decreased significantly, and the aminopyrine breath test results increased significantly after 2 weeks of treatment (P less than 0.001) and did not change thereafter. In the 9 patients treated for 15 months, alkaline phosphatase levels decreased to 63% of the basal levels and aminopyrine breath test results increased to 153% of baseline values. Transaminases, gamma-glutamyltransferase, and total bile salt levels decreased significantly after 2 weeks of treatment but returned to baseline after 3 months. No changes in bilirubin and cholesterol levels were observed. It is concluded that long-term rifampicin treatment is effective for relieving pruritus in primary biliary cirrhosis, but liver enzymes should be monitored to detect drug-induced hepatitis.

Pulmonary aspiration of gastric contents in patients receiving mechanical ventilation: the effect of body position

OBJECTIVE

To determine if the semirecumbent position (45-degree angle) decreases aspiration of gastric contents to the airways in intubated and mechanically ventilated patients.

DESIGN

A randomized, two-period crossover trial.

SETTING

Respiratory intensive care unit.

PATIENTS

Nineteen patients requiring intubation and mechanical ventilation.

INTERVENTIONS

Patients were studied in the supine and semirecumbent positions on two separate days.

MEASUREMENTS

After technetium (Tc)-99m sulphur colloid labeling of gastric contents, sequential radioactive counts in endobronchial secretions were measured at 30-minute intervals over a 5-hour period. Samples of endobronchial secretions, gastric juice, and pharyngeal contents were obtained for qualitative bacterial cultures.

RESULTS

Mean radioactive counts in endobronchial secretions were higher in samples obtained while patients were in the supine position than in those obtained while patients were in the semirecumbent position (4154 cpm compared with 954 cpm; P = 0.036). Moreover, the aspiration pattern was time-dependent for each position: For the supine position, radioactivity was 298 cpm at 30 min and 2592 cpm at 300 min (P = 0.013); for the semirecumbent position, radioactivity was 103 cpm at 30 min and 216 cpm at 300 min (P = 0.04). The same microorganisms were isolated from stomach, pharynx, and endobronchial samples in 32% of studies done while patients were semirecumbent and in 68% of studies done while patients were in the supine position.

CONCLUSIONS

We conclude that the supine position and length of time the patient is kept in this position are potential risk factors for aspiration of gastric contents. Elevating the head of the bed for patients who can tolerate the semirecumbent position may be a simple, no-cost prophylactic measure.

Comparative study of the kinetics of the renal tracers 99Tcm-MAG3 and 131I-hippuran

Serial measurements of plasma activity, plasma protein binding and urine excretion were obtained in order to study 99Tcm-MAG3 (MAG) and 131I-Hippuran (OIH) kinetics after simultaneous injection of both tracers in 21 patients with various renal diseases. Results were compared on the basis of a compartmental model, calculating the rate constants as well as the clearance and volume of distribution. Protein binding was calculated in 10 patients (mean: MAG = 54.7%, OIH = 33.8%). The dependence of time, tracer and patient factors was shown by ANOVA. Time was independent, with tracer and patient factors and their interaction being significant. The mean value of the renal excretion constant was equal for the two tracers (k12 = 0.052 min-1). The clearance values were found to be highly correlated (r = 0.982) with a ratio of 0.57 between them. The volumes of distribution in litres were 4.1 (MAG) and 7.0 (OIH). One-hour urine excretion was nearly the same for both tracers (MAG: 64%, OIH: 63% of the injected dose).

99Tcm-HMPAO leucocyte scintigraphy in the diagnosis of bone infection

The utility of 99Tcm-HMPAO leucocytes has been studied in combination with 99Tcm-MDP bone scanning in the diagnosis of bone infection in a series of 50 patients with a clinical suspicion of bone infection. Thirty-three patients were referred to our Service from the Department of Orthopaedic Surgery (Group A) and seventeen from the Infectious Disease Unit (Group B). A total of 52 lesion sites were studied. The leucocyte and bone studies were performed within four days. The leucocyte scan was obtained at 30-60 min and 4-6 h after i.v. injection of 370 +/- 74 MBq of 99Tcm-HMPAO leucocytes. After confirming the scintigraphic findings, the results obtained were: Group A, 12 true positive, 21 true negative and 2 false positive; and in Group B, 5 true positive, 9 true negative and 4 false negative. The overall sensitivity was 80.9% with a specificity of 93.7%. Although the high bone marrow activity seen with 99Tcm-HMPAO leucocytes may reduce sensitivity, very good results were obtained in bone infection. The use of 99Tcm means great progress in the radiolabelling of white blood cells in terms of availability and better image quality. The combination of 99Tcm-HMPAO leucocytes and 99Tcm-MDP can be recommended as one of the most suitable methods for use in the diagnosis of bone infection, especially in patients with previous bone disease.

Intestinal calcium absorption and parathyroid hormone secretion in asthmatic patients on prolonged oral or inhaled steroid treatment

A secondary hyperparathyroidism resulting from decreased intestinal calcium (Ca) absorption has been proposed as a contributory factor to glucocorticoid-induced osteoporosis. Inhaled steroids do not usually suppress adrenal gland function unless daily doses above 1,500 microgram are used. A recent study, however, has shown a reduced total body calcium in patients on regular beclomethasone treatment. In theory, osteopenia in these patients could be due to a direct effect of inhaled steroids on bone or due to an impaired intestinal calcium absorption. In this study, Ca absorption and parathyroid hormone (PTH) secretion were evaluated in three groups: 1) asthmatics on continuous oral and inhaled steroid treatment (11.3 +/- 4.4, range 5-33.5 mg.day-1 prednisone and 660 +/- 265, range 400-1,600 microgram.day-1 beclomethasone, respectively); 2) asthmatics on regular beclomethasone therapy (585 +/- 210, range 400-1,200 microgram.day-1); and 3) healthy subjects. The prevalence of vertebral fractures was evaluated by a spinal X-ray. No differences were found in either Ca absorption or PTH serum levels between asthmatics and healthy subjects (analysis of variance-ANOVA). Vertebral fractures were significantly more frequent in patients from group 1 (14 of 25) than in those from group 2 (2 or 25). We conclude that both prolonged oral steroid treatment and inhaled steroids, at doses lower than 1,600 microgram.day-1 do not cause Ca malabsorption, and that hyperparathyroidism does not contribute to osteoporosis in these patients.

Intestinal calcium absorption and parathyroid hormone secretion in asthmatic patients on prolonged oral or inhaled steroid treatment

A secondary hyperparathyroidism resulting from decreased intestinal calcium (Ca) absorption has been proposed as a contributory factor to glucocorticoid-induced osteoporosis. Inhaled steroids do not usually suppress adrenal gland function unless daily doses above 1,500 microgram are used. A recent study, however, has shown a reduced total body calcium in patients on regular beclomethasone treatment. In theory, osteopenia in these patients could be due to a direct effect of inhaled steroids on bone or due to an impaired intestinal calcium absorption. In this study, Ca absorption and parathyroid hormone (PTH) secretion were evaluated in three groups: 1) asthmatics on continuous oral and inhaled steroid treatment (11.3 +/- 4.4, range 5-33.5 mg.day-1 prednisone and 660 +/- 265, range 400-1,600 microgram.day-1 beclomethasone, respectively); 2) asthmatics on regular beclomethasone therapy (585 +/- 210, range 400-1,200 microgram.day-1); and 3) healthy subjects. The prevalence of vertebral fractures was evaluated by a spinal X-ray. No differences were found in either Ca absorption or PTH serum levels between asthmatics and healthy subjects (analysis of variance-ANOVA). Vertebral fractures were significantly more frequent in patients from group 1 (14 of 25) than in those from group 2 (2 or 25). We conclude that both prolonged oral steroid treatment and inhaled steroids, at doses lower than 1,600 microgram.day-1 do not cause Ca malabsorption, and that hyperparathyroidism does not contribute to osteoporosis in these patients.

Factors influencing the development of metabolic bone disease in primary biliary cirrhosis

The prevalence, type, and factors that may influence the development of bone disease in primary biliary cirrhosis, have been investigated in 20 consecutive patients, who, in addition to liver function tests and mineral and vitamin D metabolism studies, were submitted to a transiliac bone biopsy after tetracycline double-labeling for quantitative histomorphometric examination. Intestinal calcium absorption was also assessed in 16 patients. Seven patients (35%) had reduced bone volume and were considered osteoporotic. Three also had bone mineralization impairment, but did not have criteria for osteomalacia. Bone formation was depressed in 15 patients, and bone resorption was low or normal in 19 cases. Eroded surfaces were reduced in all osteoporotic patients. Duration of primary biliary cirrhosis was significantly longer in patients with osteoporosis (6.3 +/- 0.6 yr) than in those without osteoporosis (2.6 +/- 0.6, p = 0.004). Moreover, osteoporosis was more prevalent in postmenopausal women, and in those who had intestinal calcium malabsorption, which was present in 80% of osteoporotic patients but in only 18% of nonosteoporotic patients (p = 0.03). Osteoporosis and mineralization bone impairment were unrelated to the severity of cholestasis. 25-Hydroxyvitamin D was significantly lower in those patients with intestinal calcium malabsorption. The results of this study indicate that osteodystrophy in primary biliary cirrhosis is characterized mainly by "low-turnover" osteoporosis, which is related to the duration of the liver disease, postmenopausal condition, and calcium malabsorption.

Effects of intravenous amino acid infusion and dietary proteins on kidney function in cirrhosis

Acute intravenous amino acid infusion or a high-protein diet increases renal plasma flow and the glomerular filtration rate in healthy subjects. Conversely, a low-protein diet reduces renal plasma flow and glomerular filtration rate. The aim of this study was to investigate the effect of intravenous amino acid infusion and dietary proteins on kidney function in cirrhosis. Protocol 1: renal plasma flow and glomerular filtration rate were measured before and during intravenous administration of a 10% amino acid solution (0.043 ml/kg/min) to eight compensated cirrhotic patients (group 1), nine nonazotemic cirrhotic patients with ascites (group 2) and seven cirrhotic patients with ascites and functional renal failure (group 3). Amino acid administration induced a significant increase in renal plasma flow and glomerular filtration rate in all groups studied. Renal plasma flow and glomerular filtration rate increased by 16% and 14%, respectively, in group 1; 31% and 22% in group 2 and 25% and 21% in group 3. Protocol 2: Renal plasma flow and glomerular filtration rate were measured in nine cirrhotic patients with ascites after 11 days on a low-protein diet (0.5 gm/kg body weight/day) and also after the patients followed for 11 days a moderately high-protein diet (1.5 gm/kg body weight/day). The moderately high-protein diet was associated with a significant increase in renal plasma flow (12%) and glomerular filtration rate (13%) compared with values obtained while the patients followed the low-protein diet. Plasma glucagon levels increased markedly during the intravenous administration of amino acid and the intake of the moderately high-protein diet.(ABSTRACT TRUNCATED AT 250 WORDS)

Indium-111-labeled platelets in monitoring human pancreatic transplants

We have performed 59 111In-labeled platelet scintigraphies in 12 patients with pancreas transplant, and we have compared retrospectively the 111In platelet uptake with the graft immunological situation. A diffuse uptake in the graft was seen in five of six patients with pancreatic rejection. The scans became positive before changes in biochemical tests were detected. No 111In platelet uptake was seen in five of seven normally functioning grafts. Two cases of venous thrombosis and two perigraft hematomas appeared like a focal 111In platelet accumulation. Indium-111-labeled platelet scintigraphy can be a useful method for monitoring pancreas transplants. It may be helpful in the early detection of pancreatic allograft rejection and in the differential diagnosis between this and other complications such as thrombosis or hematomas.

Iron stores in essential thrombocythaemia. A study of 26 patients

The iron status of 26 patients with essential thrombocythaemia (ET) was evaluated at diagnosis by means of bone marrow iron and blood studies, including serum ferritin determination. Nine patients were males, 17 females, and the mean age was 53 years (range 7-81). A decreased or absent iron level by semiquantitative estimation on bone marrow smears was observed in 77% of patients, and 81% had a low sideroblast score. Such a marrow pattern of iron depletion was equally distributed between both sexes. Contrasting with this, normal Hb, MCV, serum iron and serum ferritin were registered in the majority of cases. According to these results, absent or decreased marrow iron would be a common feature in ET, generally not reflecting true iron deficiency, as it occurs in the remaining chronic myeloproliferative disorders. Thus, in patients in whom ET is suspected, the diagnostic criterion of ruling out iron deficiency would be better served by serum ferritin measurement than by bone marrow iron estimation.

Measurement of body water compartments after ligation of the common bile duct in the rabbit

To elucidate the pathogenesis of renal insufficiency associated with obstructive jaundice we have studied spontaneous water intake and body water compartments in rabbits undergoing common bile duct ligation. Total body water, extracellular water and plasma volume were measured by multi-isotope dilution technique. During the initial 6 postoperative days spontaneous water intake was 898 ml in sham operated animals (SO) but only 280 ml in jaundiced rabbits (OJ6) (P less than 0.01). Creatinine clearance was almost unchanged in SO but fell to 60 per cent of the preoperative values both in OJ6 and in paired-drink sham operated animals (SO2). There was a 15 per cent decrease in total body water (P less than 0.01) and a 24 per cent decrease in extracellular water (P less than 0.01) 6 days after bile duct ligation. There was a further reduction of the extracellular water to 35 per cent and a 15 per cent reduction of plasma volume 12 days after ligation. Water restriction mimicked the alterations in body composition produced by bile duct ligation. We conclude that bile duct ligation is associated with hypodypsia and a depletion of extracellular water and plasma volume. These alterations could explain the tendency to develop hypotension and renal failure which are associated with obstructive jaundice.

Comparison of rifampicin with phenobarbitone for treatment of pruritus in biliary cirrhosis

The anti-pruritic effects of rifampicin (10 mg/kg) and phenobarbitone (3 mg/kg) were assessed in 22 patients with primary biliary cirrhosis in a crossover randomised clinical trial. Each agent was given for 14 days, with a 30-day washout period between treatments. 21 patients completed the course of rifampicin and 18 that of phenobarbitone; rifampicin was withdrawn from 1 patient when anaemia and renal failure developed, whereas 3 patients stopped taking phenobarbitone because of a rash and the 4th merely refused the drug. Rifampicin had a greater anti-pruritic effect than phenobarbitone. The symptom improved in 19 patients taking rifampicin and in 8 taking phenobarbitone, the degree of improvement being greater with rifampicin than with phenobarbitone. Pruritus disappeared in 9 patients receiving rifampicin, and three of them were free of itch when switching over to phenobarbitone. Both drugs were equally effective in inducing hepatic microsomal function but rifampicin has the additional effect of reducing cholestasis. Its anti-pruritic effect should be tested in long-term clinical trials.