The sensitivity and specificity of transvaginal ultrasound with regard to acute pelvic inflammatory disease: a review of the literature.

PURPOSE: This review aims to sum up current knowledge on the sensitivity and specificity of ultrasound features suggestive of acute pelvic inflammatory disease (PID). METHODS: A PubMed database search was undertaken, using the MeSH terms "(pelvic inflammatory disease or salpingitis or adnexitis) and ultrasonography". We included original articles evaluating the performance of vaginal ultrasound in detecting acute PID. RESULTS: Seven articles were selected, including between 18 and 77 patients each. The golden standard used was laparoscopy/endometrial biopsy in six studies and mostly clinical evaluation in one. "Thick tubal walls" proved to be a specific and sensitive ultrasound sign of acute PID, provided that the walls of the tubes can be evaluated, i.e., when fluid is present in the tubal lumen (100 % sensitivity). The cogwheel sign is also a specific sign of PID (95-99 % specificity), but it seems to be less sensitive (0-86 % sensitivity). Bilateral adnexal masses appearing either as small solid masses or as cystic masses with thick walls and possibly manifesting the cogwheel sign also seems to be a reasonably reliable sign (82 % sensitivity, 83 %specificity). Doppler results overlap too much between women with and without acute PID for them to be useful in the diagnosis of acute PID, even though acutely inflamed tubes are richly vascularized at color Doppler. CONCLUSIONS: Even though the results of our review suggest that transvaginal ultrasound has limited ability to diagnose acute PID, it is likely to be helpful when managing women with symptoms of acute PID, because in some cases the typical ultrasound signs of acute PID can be detected.

Ultrasound for diagnosing acute salpingitis: a prospective observational diagnostic study.

STUDY QUESTION: What are the diagnostic benefits of using ultrasound in patients with a clinical suspicion of acute salpingitis and signs of pelvic inflammatory disease (PID)? SUMMARY ANSWER: In patients with a clinical suspicion of acute salpingitis, the absence of bilateral adnexal masses at ultrasound decreases the odds of mild-to-severe acute salpingitis about five times, while the presence of bilateral adnexal masses increases the odds about five times. WHAT IS KNOWN ALREADY: PID is difficult to diagnose because the symptoms are often subtle and mild. The diagnosis is usually based on clinical findings, and these are unspecific. The sensitivity and specificity of ultrasound with regard to salpingitis have been reported in one study (n = 30) of appropriate design, where most patients had severe salpingitis (i.e. pyosalpinx) or tubo-ovarian abscess. STUDY DESIGN, SIZE, DURATION: This diagnostic test study included 52 patients fulfilling the clinical criteria of PID. Patients were recruited between October 1999 and August 2008. PARTICIPANTS/MATERIALS, SETTING, METHODS: The patients underwent a standardized transvaginal gray scale and Doppler ultrasound examination by one experienced sonologist (index test) before diagnostic laparoscopy by a laparoscopist blinded to the ultrasound results. The final diagnosis was determined by laparoscopy, histology of the endometrium and other histology where relevant (reference standard). MAIN RESULTS AND THE ROLE OF CHANCE: Of the 52 patients, 23 (44%) had a final diagnosis unrelated to genital infection, while the other 29 had cervicitis (n = 3), endometritis (n = 9) or salpingitis (n = 17; mild n = 4, moderate n = 8, severe, i.e. pyosalpinx n = 5). Bilateral adnexal masses and bilateral masses lying adjacent to the ovary were seen more often on ultrasound in patients with salpingitis than with other diagnoses (bilateral adnexal masses: 82 versus 17%, i.e. 14/17 versus 6/35, P = 0.000, positive likelihood ratio 4.8, negative likelihood ratio 0.22; bilateral masses adjacent to ovary: 65 versus 17%, i.e.11/17 versus 6/35, P = 0.001, positive likelihood ratio 3.8, negative likelihood ratio 0.42). In cases of salpingitis, the masses lying adjacent to the ovaries were on average 2-3 cm in diameter, solid (n = 14), unilocular cystic (n = 4), multilocular cystic (n = 3) or multilocular solid (n = 1), with thick walls and well vascularized at colour Doppler. In no case were the cogwheel sign or incomplete septae seen. All 13 cases of moderate or severe salpingitis were diagnosed with ultrasound (detection rate 100%, 95% confidence interval 78-100%) compared with 1 of 4 cases of mild salpingitis. Three of six cases of appendicitis, and two of two ovarian cysts were correctly diagnosed with ultrasound, and one case of adnexal torsion was suspected and then verified at laparoscopy. LIMITATIONS, REASONS FOR CAUTION: The sample size is small. This is explained by difficulties with patient recruitment. There are few cases of mild salpingitis, which means that we cannot estimate with any precision the ability of ultrasound to detect very early salpingitis. The proportion of cases with salpingitis of different grade affects the sensitivity and specificity of ultrasound, and the sensitivity and specificity that we report here are applicable only to patient populations similar to ours. WIDER IMPLICATIONS OF THE FINDINGS: The information provided by transvaginal ultrasound is likely to be of help when deciding whether or not to proceed with diagnostic laparoscopy in patients with symptoms and signs suggesting PID and, if laparoscopy is not performed, to select treatment and plan follow-up.

Diagnostic performance of routine ultrasound screening for fetal abnormalities in an unselected Swedish population in 2000-2005.

OBJECTIVES: To determine the detection rate of fetal malformations and chromosomal abnormalities and the rate of false-positive ultrasound diagnoses at routine ultrasound examinations carried out by specially trained midwives in an unselected pregnant population from 2000 to 2005, and to describe the consequences of true-positive and false-positive ultrasound diagnoses of fetal malformations. METHODS: A retrospective analysis was undertaken of all babies born in Malmö, Sweden, between January 2000 and December 2005 by mothers residing in Malmö and of all fetuses with an ultrasound diagnosis of malformation made in the same time interval at the two units performing all routine pregnancy scans in Malmö. All women underwent two routine scans, at 18 and 32 weeks, including scrutiny of the fetal anatomy. Detection rates and false-positive rates were calculated per fetus. RESULTS: The prevalence of chromosomally abnormal fetuses was 0.31% (52/16 775); that of chromosomally normal fetuses with major and minor malformations was 1.80% (302/16 775) and 1.32% (222/16 775), respectively. The detection rate of fetuses with major malformations but normal chromosomes was 68% (205/302), with a detection rate at < 22 weeks of 37% (112/302). In addition, 46% (24/52) of all chromosomally abnormal fetuses were diagnosed before birth because a malformation was detected at ultrasound imaging, 33% (17/52) being detected at < 22 gestational weeks. In all, 68 pregnancies were terminated because of an ultrasound diagnosis of fetal malformation (0.4% of all pregnancies and 47% of the pregnancies in which a fetal malformation was detected by ultrasound examination before 22 weeks). A false-positive ultrasound diagnosis of malformation was made in 0.19% (31/16 180) of the normally formed fetuses and in 20 (0.12%) fetuses the abnormal finding persisted during pregnancy. No fetus assigned a false-positive diagnosis was lost by termination of pregnancy, but most were subjected to one or more unnecessary interventions before birth (e.g. amniocentesis), at birth (e.g. Cesarean section) or after birth (e.g. electrocardiogram, X-ray, ultrasound examination or treatment with antibiotics). CONCLUSIONS: In a screening program consisting of one fetal anomaly scan at 18 weeks and another at 32 weeks the detection rate of major malformations in chromosomally normal fetuses was 68% with a detection rate of 37% at < 22 weeks. The corresponding detection rates of chromosomally abnormal fetuses were 46% and 33%. Fewer than one in 500 screened fetuses had an ultrasound diagnosis of an anomaly that was not confirmed after birth.