Patients with Lemierre syndrome have a high risk of new thromboembolic complications, clinical sequelae and death: an analysis of 712 cases

BACKGROUND

Lemierre syndrome is characterized by head/neck vein thrombosis and septic embolism usually complicating an acute oropharyngeal bacterial infection in adolescents and young adults. We described the course of Lemierre syndrome in the contemporary era.

METHODS

In our individual-level analysis of 712 patients (2000-2017), we included cases described as Lemierre syndrome if these criteria were met: (i) primary site of bacterial infection in the head/neck; (ii) objectively confirmed local thrombotic complications or septic embolism. The study outcomes were new or recurrent venous thromboembolism or peripheral septic lesions, major bleeding, all-cause death and clinical sequelae.

RESULTS

The median age was 21 (Q1-Q3: 17-33) years, and 295 (41%) were female. At diagnosis, acute thrombosis of head/neck veins was detected in 597 (84%) patients, septic embolism in 582 (82%) and both in 468 (80%). After diagnosis and during in-hospital follow-up, new venous thromboembolism occurred in 34 (5.2%, 95% CI 3.8-7.2%) patients, new peripheral septic lesions became evident in 76 (11.7%; 9.4-14.3%). The rate of either was lower in patients who received anticoagulation (OR: 0.59; 0.36-0.94), higher in those with initial intracranial involvement (OR: 2.35; 1.45-3.80). Major bleeding occurred in 19 patients (2.9%; 1.9-4.5%), and 26 died (4.0%; 2.7-5.8%). Clinical sequelae were reported in 65 (10.4%, 8.2-13.0%) individuals, often consisting of cranial nerve palsy (n = 24) and orthopaedic limitations (n = 19).

CONCLUSIONS

Patients with Lemierre syndrome were characterized by a substantial risk of new thromboembolic complications and death. This risk was higher in the presence of initial intracranial involvement. One-tenth of survivors suffered major clinical sequelae.

Fresh and cryopreserved arterial homografts in the treatment of prosthetic graft infections: experience of the Italian Collaborative Vascular Homograft Group

Following the experience of cardiac surgeons with homografts in the treatment of infective aortic valve endocarditis, cardiovascular surgeons have investigated in situ revascularization by means of homografts in the management of vascular prosthetic graft infections. Preliminary results are encouraging, but their late fate in long-term follow-up and the influence of preservation techniques are still under investigation. This article reports the experience of the Italian Collaborative Vascular Homograft Group, with the use of fresh and cryopreserved arterial homografts for the treatment of prosthetic graft infections. Between March 1994 and December 1996, 44 patients with prosthetic graft infection were treated with homografts (13 preserved at 4 degrees C, 31 cryopreserved). The mean age of the patients was 65 years. Emergency surgical procedures were performed in eight patients (18%). Sepsis was diagnosed in 11 patients, aortoenteric fistula in 13, and false aneurysms in 10. Staphylococcus was the main cause of infection. The types of vascular reconstruction with homograft were: 32 aortobifemoral, 3 aortoaortic, 2 iliofemoral, 4 peripheral, and 3 axillobifemoral. Human lymphocyte antigen (HLA) and antibody (ABO) blood group system compatibility between donors and recipients was not respected. The mean duration of follow-up was 15 months (range 1-33). Clinical and duplex scanning evaluations were routinely performed. Computed tomography (CT) or magnetic resonance (MR) scanning or arteriography were performed on the basis of duplex scanning results. There were six deaths during the early postoperative period (30 days) with a mortality rate of 13.6%. During the follow-up there were five late deaths with a mortality rate of 11.4%. Eight patients had graft occlusion. Three cases were successfully treated with thrombectomy. Two cases were successfully treated with femoropopliteal bypass with autologous vein. In three cases leg amputation was necessary. The results of fresh and cryopreserved homograft were compared. No significative differences of early postoperative mortality, late mortality, homograft related mortality, and graft occlusion were observed. We have evaluated the actuarial survival of the patients and the actuarial patency of the homografts on the aortoiliac reconstructions. Twelve months after the surgery the actuarial survival of the patients was 73% and the actuarial patency of the homografts was 56%. In our preliminary experience, we have not observed any significant difference in terms of clinical outcome by using fresh rather than cryopreserved homografts. In the near future it will be our policy to employ only cryopreserved homografts. Moreover, we will extend vessel harvesting to nonheart-beating donors, thus maximizing retrieval. The aforementioned solutions will supply the best graft availability to obtain dimensional and ABO compatibility between donors and recipients.

[Our experience concerning scrotal traumatology]

The Authors present their experience on 24 blunt scrotal traumas observed since January 1991. They underline the importance of an ecographic scanning that enables a precise evaluation of the traumatic event. Patients that present positive ultrasonic findings are promptly operated thus permitting bleeding and infection control. In this way gonadic function is restored and hospital care reduced. The diagnostic approach is presented, cases reported and results discussed. After a review of the literature on the topic they stress the role of Eco-Color-Doppler examination in scrotal blunt trauma for the intrinsic characteristics of precision, rapidity and non invasivity. This permits a nosologic evaluation of all types of blunt trauma and selects, for surgery, only those patients with a well definied diagnosis.

[Epidemiological study of mortality in a cohort of rayon industry employees]

A cohort of 166 employees in the SNIA viscosa rayon production plant in Padua was followed up for mortality up to 1989. The study detected a statistically significant increase in total mortality mainly due to an excess of deaths from ischaemic heart diseases (ICD 410-414). Workers affected by occupational disease in the age group 50-64 years had the highest risk with a threefold increase in mortality compared to the general population. An increasing pattern of lung cancer mortality with time since first exposure was observed. The SMR for lung cancer was 192 for smokers with occupational disease.

Color Doppler imaging of liver metastases. The value phase-III of a US contrast agent: SH U 508 A (Levovist) Schering

In a phase-III multicenter clinical trial, the color Doppler vascular patterns were studied of 34 liver metastases in 18 patients before and after the i.v. injection of SH U 508 A (Levovist), with different US units and probes. The patients were selected as having poor color Doppler signals at unenhanced examinations. Lesion size ranged .8 to 9 cm (mean: 3.5 cm). The primary lesion site was the colon in 14 cases, the breast in 8 cases, the lung in 4, the stomach in 4 cases, the ovary in 3 and finally unknown in 4 cases. Each patient received two to four contrast agent injections, with suggested doses and concentrations (10 ml x 300 mg/ml, 8 ml x 400 mgr/ml). No adverse reactions were observed. Thirteen of 34 lesions exhibited no vascular signals at baseline examinations, 10 exhibited some perilesional color spots or small vessel branches, 5 some internal color spots or vessels and 4 small internal and peripheral vessels. After contrast agent infusion, the vascular patterns were better demonstrated in 28/34 lesions and the signal-to-noise ratio was markedly improved, in a concentration-dependent manner, from 40 to 240s. Five lesions remained avascular, 11 exhibited "basket"-like vascular patterns, 10 "internal flow" patterns and finally 10 lesions exhibited both. No major correlation was observed between vascular pattern and lesion size. To conclude, the use of the intravenous contrast agent SH U 508 A (Levovist) appears to be a promising technique to improve the color Doppler demonstration of focal metastatic liver lesions. Nonetheless, further studies on larger series of cases are needed to differentiate the different primary sites of the metastases.

[The combination of extracorporeal lithotripsy and percutaneous nephrostomy in the treatment of obstructive ureteral urate calculi]

The authors report their experience with combined percutaneous nephrostomy and extracorporeal shock-wave lithotripsy to treat obstructive uratic ureteral stones. The role of nephrostomy is stressed as a diagnosis and treatment method before, during and after lithotripsy. Thus, the method proved especially useful to drain obstructed kidneys and restore peristalsis, to evacuate septic urine, to facilitate the elimination of lithiasic fragments, to perform anterograde pyelography before, during and after lithotripsy and finally to allow pharmacological litholysis. Fourteen patients were successfully treated with combined extracorporeal lithotripsy and percutaneous nephrostomy and the results compared with those obtained with other techniques--e.g., ureteroscopy, whose value appears lower because the method requires general anesthesia and is more traumatic to the ureter. The authors conclude that combined extracorporeal lithotripsy and percutaneous nephrostomy make the best technique to treat obstructive uric acid stones thanks to their positive results, low invasiveness and to patients compliance.

[Doppler color-echo in the echographic evaluation of solid neoplasms of the breast: 5 years of experience]

In the last 5 years, 1,245 breasts have been examined with conventional and color-Doppler US. To assess color-Doppler capabilities and limitations, the results were critically reviewed only of the 311 patients who were operated and had unquestionable histologic findings. We investigated: 1) the number of "vascular poles", that is the vessels entering the examined mass from the periphery; 2) the presence of vessels with "abnormal" features, that is the vessels with varying diameters and/or with tortuous and erratic course; 3) the presence of vessels even on the mass interface only. The criterion indicated as no. 1, that is the presence of more than a vascular pole, exhibited 90.4% sensitivity and 70.7% prospective and 90.7% retrospective specificity. The criterion indicated as no. 2, that is the presence of vessels with anomalous features exhibited 75.1% sensitivity and 96.9% specificity. Using criterion no. 3 instead of no. 1, sensitivity would be increased from 90.4% to 96.5% but specificity would be decreased from 70.7% (and 90.7% retrospective specificity) to 46.9%, which was considered to be too low relative to the moderate increase in sensitivity. The positive predictive value of the presence of two vascular poles was 85% and that of the presence of vessels with anomalous course was 97.7%. Criteria no. 1 and 2 had 70.7% and 68.8% negative predictive value, respectively. In conclusion, the authors suggest the use of color-Doppler US to add further pieces of information to those obtained with conventional US.

Il contributo dell'eco color doppler nella valutazione dello scroto acuto

The Authors report their experience in the use of Echo color Doppler in acute scrotum. The study is based on the treatment on 121 patients from 2 to 43 years (mean 19 years) affected by acute scrotal disease using an Acuson 128 with a 7 MHz linear probe and a Doppler frequency of 5 MHz. Of 57 patients with a clinical diagnosis of acute torsion of the spermatic cord only 21 (36.8%) had an absence of blood flow confirmed echographically. In 55 patients with a clinical diagnosis of acute epididymal flogosis, 46 (83.6%) were confirmed echographically. In the other subjects 5 acute spermatic cord torsion (9.1%), 2 hematomas in testicular neoplasia (3.6%) and 2 spontaneous hematomas were discovered. In the remaining 9 cases, wjth a history of scrotal trauma, the echographic patterns showed a scrotal hematoma and the integrity of the tunica albuginea or the lack of it. After having compared the US color Doppler with other instrumental techniques for acute scrotum, the Authors conclude by considering this procedure the most indicated for all acute scrotal diseases.

[Color-Doppler in the study of male sexual impotence]

The authors report their experience with color-Doppler US in the study of 54 male patients with sexual impotence. The examination includes two distinct phases; in between, the erection-inducing drugs is injected directly in the cavernous bodies. During the basal phase, B-mode information relative to both morphology and structure of cavernous bodies is collected. After injecting the drug, systolic and end-diastolic velocities are evaluated as flowmetric indices, together with the resistive index; these variables are derived from cavernous arteries, at scheduled time--i.e., 5, 10 and 20 minutes after the injection. Moreover, the examined patients were divided into 4 groups according to their clinical response to the pharmacologic test. Color-Doppler US proved to be quite sensitive in the identification of the patients with a vascular alteration, both venous and arterial, underlying their erectile dysfunction; as a matter of fact, venous flights are easily depicted with the use of colors. The authors believe that color-Doppler could eventually become a major exam in the diagnosis of sexually impotent patients, thus allowing the marked reduction of such invasive diagnostic techniques as selective angiography of internal pudendum arteries and dynamic cavernosography, which are poorly tolerated by the patients.

Risk factors for varicose disease before and during pregnancy

Risk factors for varicose disease before and during pregnancy have been analyzed by use of data from a survey on venous disease in pregnancy conducted in 611 women (mean age thirty years, range fifteen to forty-seven) who consecutively delivered at the Obstetric-Gynecologic Clinic "L. Mangiagalli" of Milan between January and April, 1989. In total, 137 women (22%) reported varicose disease before the index pregnancy. The relative risk (RR) of varicose disease before the index pregnancy increased with age, being, as compared with women aged twenty-nine years or less, 1.6 in those aged thirty to thirty-four and 4.1 in those aged thirty-five years or more (chi 2(1) trend 25.28, p < 0.001). Compared with nulliparae, women reporting a full-term pregnancy before the index pregnancy had an RR of venous disease of 1.2, and the risk increased to 3.8 in women reporting two or more births (chi 2(1) trend 25.28, p < 0.001). A family history of varicose disease was associated with an RR of venous disease of 6.2 (95% confidence interval, CI, from 4.1 to 9.6). No relationship emerged between varicose disease and overweight. Of the 474 women who did not report venous disease before the index pregnancy, 132 (28%) developed venous disease during the index pregnancy. The risk of developing venous disease in pregnancy increased with age, being, as compared with women aged twenty-four years or less, 4.0 in those aged thirty-five years or more, and the trend in risk was statistically significant (chi 2(1) trend 16.25, p < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)

[Role of echo-color Doppler in the diagnosis of breast diseases. Personal experience]

The role of color-Doppler US was investigated in the diagnosis of solid focal breast lesions. The results obtained with this method over the last two years were reviewed. Seventy-two patients with solid breast lesions were considered: conventional US scans of the nodules were performed first and color-Doppler scans followed, to depict vascularization. In benign focal lesions color-Doppler US never demonstrated more than a single vascular pole afferent to the lesion. In 92.5% of histologically malignant lesions, color-Doppler US easily demonstrated two or more feeding vessels. The analysis of our series confirmed the presence of a typical vascular pattern related to breast carcinoma which is easy to depict by means of color-Doppler US: this new technique is therefore of great value in the differentiation of benign from malignant breast masses, especially in the cases where conventional US and mammography alone failed to yield unquestionable and final results.

[Clinical applications of color-Doppler: the parathyroid glands]

The high-resolution appearance of enlarged parathyroid glands is well known. Thus, real-time gray-scale US alone fails to provide, in ENT surgery, adequate sensitivity and specificity rates to differentiate between parathyroid glands, hypoechoic thyroid adenomas and other hypoechoic neck masses. Since parathyroid tissue, in both normal and enlarged glands, is hypervascular, color-Doppler US is used as a sort of non-invasive angiography to identify parathyroid glands. The combined use of B-mode and color-Doppler US allows the vascular features of thyroid masses to be satisfactorily demonstrated, with easy differentiation between enlarged parathyroid glands, featuring diffuse internal vascularization, and thyroid adenomas characterized by rounded peripheral vessels and also lymph nodes and cysts exhibiting different vascular patterns. We studied 25 patients with clinical and biochemical signs of hyperparathyroidism (19 primary and 6 secondary) submitted to surgery in the last 20 months. Every patient was scanned with both B-mode and color-Doppler US. At surgery, 19 parathyroid adenomas were found--16 of them correctly identified preoperatively with color-Doppler US and 3 false negatives (retrotracheal glands). Moreover, 1 false positive was observed due to a small Plummer's adenoma misdiagnosed as an intrathyroid parathyroid adenoma: both lesions had the same vascular pattern on US images. Sensitivity was 84.5% and specificity 93.7%. In secondary HPT patients, 23 hyperplastic glands were found at surgery--21 of them correctly identified preoperatively by color-Doppler US, with 2 false negatives. No false positive was found. Sensitivity was 87.5% and specificity 100%. Sensitivity does not differ very much from what reported in literature. Specificity is clearly increased by the use of color-Doppler US. The possible source of error represented by Plummer's adenomas lead us to investigate pulsed Doppler capabilities in differentiating Plummer's adenomas from PT glands, since color-Doppler findings were similar in the two conditions. Peak velocities recorded with both color and pulsed Doppler showed velocity to range 6 to 40 cm/s in parathyroid glands (mean +/- SD: 14.6 +/- 11.7) and 38 to 120 cm/s in thyrotoxic nodules (mean +/- SD: 78.4 +/- 23). The statistical analysis of the results showed a highly significant difference between the two groups of velocities. Peak velocities as recorded in the main, vessels of the parathyroid glands with color and pulsed Doppler were correlated with the activity of the parathyroid glands.(ABSTRACT TRUNCATED AT 400 WORDS)

[Ultrasound-color Doppler in the study of sexual impotence]

Male impotence is a relatively frequency disease. To define the correct aetiology of this disorder is important to plan a right diagnosis to difference organic, psychological and psycho-organic causes. From June 90 to June 91 fifty-four patients with male impotence of different degree were observed and went through diagnostic investigations. The patients were classified in four groups (A, B, C, D) as clinical results of the pharmacological test (intracavernous injection of PGE1 alpha 15 micrograms). A and B groups showed normal and nearly normal hemogenic finding. C group showed either low arterial flow increase after FIC or venous leakage. D group showed very low haemodynamic increase. The analysis of Eco-doppler studies was performed 5'-10'-20' after intracavernous injection of PGE1 alpha obtaining three haemodynamic markers: the systolic top flow (Vs) the diastolic ending flow (Vd) resistance flow index. The Authors discuss the results obtained considering the Eco-color-doppler the most important stage in the haemodynamic evaluation of sexual impotence.

[A new inclusion complex of silibinin and beta-cyclodextrins: in vitro dissolution kinetics and in vivo absorption in comparison with traditional formulations]

The very low bioavailability of silybinin, the main constituent of silymarin, so far prevented the development of an oral pharmaceutical specialty based on this active ingredient. To overcome this difficulty, an inclusion complex between Silybinin and beta-Cyclodextrin was prepared. The new complex was compared in vitro tests (dissolution rate) and in a in vivo test (rat bile elimination) with silybinin, silymarin and one traditional formulation based on silybinin. The results show a dramatic increase in the dissolution rate of the complex (> 90% within 5 min) respect to the silybinin that confirm to be practically insoluble (< 5%). The in vivo results agree with the dissolution rates; after administration of the silybinin complex p.o., the silybinin concentration in the rat bile was near 20 times more than after administration of silybinin as is or in a traditional formulation. In the last two cases, the silybinin concentration was even 6 times less than after administration of the same amount of silymarin. These data show that the beta-CD complex solved the problem of the bioavailability of silybinin which, in the traditional formulation utilised as reference, proved to be not bioavailable.

[Epidemiological analysis of the incidence of varicose pathology in pregnancy]

One thousand and fourteen women who were delivered in the Obst. Gynec. Clinic "L. Mangiagalli" were investigated to evaluate the real incidence of varicose disease, its correlation with some factors and the development of complication. The observation period was comprised between the 1st and the 4th day of puerperium in which women were investigated by obstetricians through a detailed questionnaire and underwent an angiological visit. The mean age of the puerperae was 29.6 years (range 15-47 yrs); 587 women were primiparas (57.9%). The prevalence of varicose disease's different aspects resulted 57.9%, while the incidence related to pregnancy was 26.1%. The prevalence and the incidence resulted to be respectively 26.8% and 14.4% for varicosities, 5.6% and 3.1% for saphenous varicosis. Complications were observed in 10 patients (0.99%). 45.3% of patients reported family positivity for varicose disease; this group has shown a statistically significant difference (p less than 0.01) for the onset of different aspects of varicose syndrome.

[Portal hypertension of hepatic origin. A qualitative assessment by color and echo Doppler US]

One hundred and twenty-eight subjects were studied: 103 of them were affected with portal hypertension diagnosed both radiologically and clinically. Twenty-five healthy subjects were studied, as a control group, by means of combined real-time US and color Doppler. US parameters were evaluated, specific to chronic hepatopathy, together with the Doppler qualitative parameters relative to splanchnic vessels hemodynamics. Our results allowed a sort of noninvasive angiogram of the portal system to be obtained, which is to be of use for diagnosing portal hypertension, and for assessing its causes, risks, and consequences. This study was also aimed at suggesting an examination protocol for portal hypertension, employing real-time and color Doppler US, which any radiologist with enough experience in abdominal US could use. Color Doppler, although not strictly necessary to obtain good results, dramatically shortens execution times. Moreover, color Doppler allows the method to be more quickly learned.

[Color Doppler in the echographic evaluation of breast nodules]

The authors report on their experience with color Doppler sonography in the diagnosis of solid breast masses. Twenty-two patients were examined; breast masses were studied with B-mode US first, and then with color Doppler US to evaluate eventual tumor vascularization. Color Doppler US demonstrated only one vascular pole in histologically confirmed benign masses. On the contrary, in 92.8% of histologically confirmed malignant masses, color Doppler easily depicted 2 or more groups of nutritional arteries. Color Doppler makes the diagnosis of malignant masses easier, thus allowing, in the author's opinion, a reduction in the number of biopsies of solid breast masses clinically/mammographically detected. The use of color Doppler US is therefore suggested: the technique is noninvasive, fast, and easy and its widespread use would translate into advantages for both the patient and the clinician.

[Doppler color in the echographic study of hyperplastic parathyroid glands]

The sonographic examination of hyperplastic parathyroid glands is a well-known and appreciated technique. However, its diagnostic contribution is still somehow inadequate, due to the difficult differential diagnosis of the various solid hyperechoic nodular structures in the neck and to the presence of frequently ectopic glands. The combined use of B-mode and color-Doppler US allows the vascular features of suspicious parathyroid nodules to be satisfactorily demonstrated. Higher sensitivity and specificity than conventional US are the main advantages of this technique. Still, further research is needed for B-mode color-Doppler US to actually replace fine needle biopsy in confirming the diagnosis.

Inhibition of platelet aggregation by a new agent, 5-(Z,E)-13,14-didehydro-20-methyl-carbo PGI2 (FCE 22509)

FCE (+)22509, a chemically stable carboprostacyclin analogue, inhibited in vitro ADP-induced platelet aggregation in rat platelet-rich plasma (PRP) (IC50 = 7.7 ng/ml). Subcutaneous administration of the drug, inhibited both ADP-induced platelet aggregation in rat PRP (ED50 = 0.26 mg/kg) and mortality of mice induced by collagen plus adrenaline (ED50 = 0.35 mg/kg). The compound had no such preventive effects when given orally.

Biochemical and electrophysiological study of subjects with a history of past lead exposure

The effects of lead on porphyrin metabolism and peripheral nervous system were studied in a group of 38 subjects who had not been exposed for a period of time, ranging from 3 to 27 years. The mean values for blood lead (PbB), chelated lead(PbUEDTA), and free erythrocyte protoporphyrin (FEP) were found to be significantly higher in the subjects with past lead exposure than in controls. In all cases the neurological examination was negative. The mean values for maximum motor conduction velocity (MMCV) and conduction velocity of the slower fibers (CVSF) of the ulnar and peroneal nerves were found to be significantly lower in the subjects with past lead exposure than in the control group of 23 subjects standardized for age. Signs of partial denervation were present in four cases, with two presenting a decrease of the motor conduction velocity (MCV) as well. No correlation was found between electrophysiological findings and biochemical indicators of dose and effect. The length of exposure showed a significant negative correlation only with the MMCV of the ulnar nerve. A significant difference from controls standardized for age was observed only in subjects with exposure of more than 6 months for all the electromyographic (EMG) parameters. It does not appear that the EMG findings could depend upon modest lead deposits still present in the organism; they should rather give evidence to the permanent effect of alterations that occurred during the prolonged exposure to lead.

Chronic peripheral neuropathy in workers with previous exposure to carbon disulphide

Two groups of viscose rayon production workers were examined 10 years after discontinuation of exposure to CS2. Group A comprised 20 subjects exposed to high CS2 concentrations and group B 13 subjects with lower exposure. Clinical findings and the measurements of nerve conduction velocity of the slow fibres in the peripheral nerves were evaluated. Twelve subjects had both clinical and electromyographic evidence of neuropathy and 10 showed a diminution in motor conduction velocity. A relationship between the degrees of exposure to CS2 and prevalence of polyneuropathy was found. On re-examining 12 subjects with neuropathy who had been examined four years before no significant electromyographic improvement was observed. These findings are consistent with a permanent axonal neuropathy caused by carbon disulphide.

Biological monitoring of workers with past lead exposure. Biochemical findings

In 56 subjects with lead exposure that had terminated at least 3 a previously and in a reference group of nonexposed subjects, the behavior of several biochemical indicators of dose and effect were studied. The mean values for blood lead (PbB) (1.4 +/- 0.4 mumol/l), chelatable lead (PbUEDTA) (3.4 +/- 1.5 mumol/24 h) and free erythrocyte protoporphyrin (FEP) (62 +/- 25.2 micrograms/100 ml red blood cells) were found to be significantly higher in the subjects with past lead exposure than in the referents. The cut-off levels (mean + 2 SD calculated for the reference group) of PbB, PbUEDTA and FEP were exceeded in 35.7, 67.9, and 28.6% of the exposed subjects, respectively. A normalization of lead doses and indicators of effect was reached only when the exposure had not exceeded 2 a. The time elapsed after termination of exposure did not significantly reduce the PbB level and PbUEDTA excretion, whereas these parameters correlated significantly with the length of exposure. A close correlation was found between the PbB and the PbUEDTA. Due to poor sensitivity at PbUEDTA values of less than 5.3 mumol/24 h (91% of the cases), PbB and FEP were not useful for subjects whose exposure had terminated more than 3 a earlier. In these cases, only PbUEDTA was capable of revealing elevated active lead deposits.

1-Halobenzyl-1H-indazole-3-carboxylic acids. A new class of antispermatogenic agents

The synthesis of a series of halogenated 1-benzylindazole-3-carboxylic acids and related derivatives is described. These compounds were studied for their effect on testicular weight and on the inhibition of spermatogenesis. Many of the derivatives, but in particular 1-(2,4-dichlorobenzyl)-1H-indazole-3-carboxylic acid (11), 1-(2,4-dibromobenzyl)-1H-indazole-3-carboxylic acid (13), 1-(4-chloro-2-methylbenzyl)-1H-indazole-3-carboxylic acid (27), and their glycerol esters, showed potent antispermatogenic activity.