AUB

Systematic Approach to Investigation Overview

http://www.medscape.com/viewarticle/753128_2

In the reproductive years, chronic AUB is defined as bleeding from the uterine corpus, that is abnormal in duration, volume, and/or frequency and has been present for most of the last 6 months.[1] Investigation of a given patient experiencing AUB is usually best performed in a systematic fashion designed to consider the spectrum of potential etiologies delineated in the International Federation of Gynecology and Obstetrics PALM-COEIN classification system that include polyps, adenomyosis, leiomyomas, malignancy (and hyperplasia), coagulopathies, ovulatory disorders, endometrial dysfunction, and iatrogenic causes.[2,3] The widely accepted basic investigations for chronic AUB are generally well described in relevant textbooks,[4,5] but recent international review has highlighted several areas that merit fresh attention. In routine clinical practice, the key aims of AUB investigations include the following:

1. Confirmation of the degree of HMB or other AUB and related symptoms and signs by leading questions
2. Determination of the clinical impact of the symptom on the individual patient (e.g., iron deficiency or anemia with HMB; interference with lifestyle, etc.)
3. Evaluation of the patient for the underlying cause(s) of the symptoms using a systematic approach designed to be appropriately comprehensive and capable of evaluating the patients for genital tract malignancy

A special circumstance exists in the presence of acute abnormal uterine bleeding, which has been defined as bleeding of sufficient severity to warrant urgent intervention.[1] For such bleeding, the primary aims are threefold, and investigation is critically integrated with management:

1. Cardiovascular assessment and stabilization as appropriate
2. Assessment of the most likely underlying cause(s) including evaluation for the presence of a pregnancy
3. Initiation of steps designed to reduce or stop the bleeding.
   

Investigations for the cause of AUB in a given patient begin with inquiry by a health-care provider about the validity of a symptom or sign, preferably by the use of both standardized and individualized leading questions. Indeed, many aspects of the history are important for categorization of the causes of the bleeding. For example, cyclical, predictable menstruation is usually associated with ovulation, whereas irregular and unpredictable bleeding is a typical symptom of ovulatory disorders (AUB-O). More or less detailed inquiry will be followed by the application of relevant and available investigative techniques that usually comprise a combination of blood tests and imaging of the uterus, with one or a combination of hysteroscopy and ultrasound techniques. Such investigation is usually designed to assess the effects of the symptom and to establish the potential underlying cause of the AUB. The testing routine is critically determined, in part, by the local availability of resources (see later).

The Menstrual History

The history should provide important clues to the type of AUB and to the extent of bleeding when HMB is part of the symptom complex. For chronic AUB, it is essential that the provider clearly determine the duration of the clinical problem in months or years as well as the cycle length in days, the predictability of onset of bleeding, and the duration and rate of the bleeding episodes, including the number of heavy days and the passage of clots. These questions assist in several factors including determination of the ovulatory status of the patient and, should heavy bleeding be a lifelong problem, clues of an underlying coagulopathy. For those women who experience IMB in the context of predictable cyclic menses, a focal lesion such as an endometrial polyp is often found (AUB-P).[6] Determination of the amount of blood is discussed further in the next section.

The other goal of the interview is to obtain a clear idea about the patient's concerns, expectations, and needs. Included in this evaluation is identification of the impact on her work and personal life, and the presence or absence of associated symptoms such as dysmenorrhea and fatigue that is usually secondary to anemia.

The efficiency and quality of the initial case history can often be improved by the use of a simple questionnaire, with leading questions translated into the local language and tested to ensure understanding in the context of the local culture.[7,8] Ideally this simple questionnaire should be administered before consultation with the health professional. The degree to which this case history can be extended will depend on the time available for each consultation.

Determination of the Extent of Blood Loss and Impact on Quality of Life

Although measurement of the degree of menstrual blood loss would be desirable with any complaint of HMB, it is difficult to determine regardless of the cultural setting. In routine clinical practice, attempts at accurate measurement of menstrual blood loss volume are impractical and, in general, unnecessary. Whether or not the woman has genuine HMB, she has one or more perceived symptoms that require management. Consequently it is recommended that evaluation of the AUB should be based on a patient's reported heaviness, frequency, regularity, and duration of bleeding[9,10] in conjunction with the perceived impact on quality of life and general functioning.[8,11,12] The aspects of AUB, and especially HMB, that worry women most include the psychological irritation associated with the bleeding and the complex of accompanying symptoms, especially pelvic pain, the failure to always contain the gushes of menstrual loss, and the lifestyle behaviors that need to be taken to try and contain loss.[8,13] Health workers can gain additional information about these factors by asking leading questions.[7,8]

Work is ongoing to develop a simple structured menstrual questionnaire for use in clinical practice that will assist with assessment of blood loss, total menstrual fluid loss, lifestyle factors, and a starting guide to possible underlying causes.[7] At the present time, it is recommended that a series of simple questions be asked that encompass as many of the following as practicable: Frequency of changing "menstrual protection" items, use of "double" protection; changing menstrual protection at night; self-consciousness about odor; inability to contain "gushes" of menstrual flow; embarrassment at being unable to contain "gushes" of flow, and preparations and rituals to prevent embarrassing episodes.[1,12,13] There exists recent evidence that, in the context of a clinical trial at least, these cues can allow a woman to recognize a ≥30% reduction in blood loss.[14]

Pelvic Examination

The physical examination may identify potentially relevant pathology and other features that may influence the investigational and/or treatment plan. Most gynecologists and many family practitioners have been well trained in the principles of bimanual pelvic examination, with the expectation that they will be able to apply these skills for the detection of local and generalized pelvic tenderness, large uterine fibroids, severe adenomyosis, large ovarian cysts, and significant deep invasive endometriotic nodules. However, even these pelvic signs are picked up with low sensitivity and specificity in most situations, especially when influenced by obesity and the nervous patient. Although postgraduate training improves the accuracy of this examination,[15] practitioners should be aware it usually provides only minimal clinical information above and beyond that provided by a good clinical history, and it does not provide any information about pathology having an impact on the endometrial cavity. Indeed, the findings rarely change the direction of planned investigations or future management.

Whereas physical examination is limited for the identification of intracavitary causes of AUB, it is of great value in the evaluation of the cervix. The presence of benign or malignant cervical disease may be initially suspected by the characteristics of the presenting bleeding pattern and related symptoms. However, the practitioner should have available vaginal speculums of appropriate design and size for cervical inspection across the spectrum of parity, vaginal length, and body mass index that may be encountered. Where appropriate, facilities should be available for inspection with a colposcope and histopathological evaluation of tissue biopsies, important for the diagnosis of premalignant and early malignant lesions.

Laboratory Assessment

Evaluation for coagulopathies that may contribute to HMB (AUB-C) is important in any setting because good evidence exists for a significant prevalence of these disorders in several developing[16,17] and developed countries.[18,19,20] Testing for coagulation disorders should be considered in women who have had excessively HMB since menarche and have a personal or family history suggestive of a bleeding disorder.[12] Administration of the well-validated, simple questionnaire for disorders of coagulation developed by Kadir and colleagues should has been demonstrated to be highly sensitive for the presence of coagulopathies (Table 2).[18,19,20,21] Patients determined at high risk for coagulopathy based on this instrument should undergo evaluation for coagulopathy, if possible in conjunction with a hematologist, where assays may be obtained for von Willebrand factor, ristocetin cofactor, and several other disorders as appropriate.

Evaluation of the Uterus

Comprehensive evaluation of the uterus is an integral component of the evaluation of patients with AUB. Conceptually, it is important to consider three components when evaluating the uterus:[1] assessment of the endometrium for the presence of hyperplasia or malignancy;[2] visualization of the endometrial cavity and cervical canal for localized lesions such as polyps and submucous leiomyomas; and evaluation of the structure of the uterine wall, including both the cervical stroma and the myometrium, for adenomyosis, leiomyomas, and, more rarely, arteriovenous malformations.[3] Because it is not necessary to evaluate all components in every patient, it is an important acquired clinical skill to ascertain when and how to perform complete uterine evaluation, especially with the introduction of newer imaging and endoscopic technologies.

The Role of Ultrasound Currently, initial imaging of the uterus is almost always undertaken with transvaginal ultrasound (TVUS). Ultrasound scanning has now become such a routine part of the investigation of pelvic symptoms in moderate and high-resource settings that most primary care and many specialist physicians uncritically accept the printed report describing the findings as an accurate depiction of the anatomical situation. TVUS is undoubtedly the primary imaging modality for evaluation of a range of structural abnormalities of the reproductive tract (Table 3). However, it is very clear that the quality of the assessment, and especially the interpretation, are highly dependent on the skill and experience of the ultrasound operator.

Several advanced TVUS developments have improved our ability to detect and define certain structural lesions. These advances include saline infusion sonography (SIS), color-flow Doppler assessment, and three-dimensional (3D) imaging techniques. Numerous articles have been published on all of these variations of pelvic ultrasound imaging, and it is apparent that the quality of the imaging, the interpretations, and analysis are quite variable.[22,23] Several excellent reviews and prospective studies were designed to define the accuracy of detection or exclusion of lesions in expert hands, usually by comparison of conventional TVUS with SIS and diagnostic hysteroscopy.[24,25] Although results of individual studies are variable, all three tests are moderately accurate in detecting intrauterine pathology. Direct comparison suggests that diagnostic hysteroscopy is significantly better than the other two techniques at detecting endometrial and intracavitary lesions, and that SIS is better than conventional TVUS.[24,25]