In this article, the author looks at undiagnosed chronic pelvic pain and how to investigate the symptoms


Dr Jane Wilcock, Silverdale Medical Practice, Salford CCG, co-year 3-4 Director and Tutor, University of Liverpool School of Medicine 


Chronic pelvic pain is defined as an intermittent or constant pain in the lower abdomen or pelvis for a period of at least six months, not occurring exclusively with menstruation or intercourse, and not associated with pregnancy.1 It is a global problem with prevalence rates of 5.7%-26.6% depending on the study2 and is therefore likely to be as common as chronic migraine and backache in our practice populations. It may have more than one aetiology and about 70% of cases are thought to be remedial, leaving 30% of women with non-remedial pain.

This article reviews the approach, aetiology and investigations for women presenting in general practice with chronic pelvic pain and highlights the differences in premenopausal and postmenopausal diagnostic hypotheses. A diagnosis of six months of pelvic pain can only be made retrospectively. GPs will make the diagnosis much earlier if, after initial investigations, they can identify the likely probability of disease, individual patient pain features, psychological and social contexts.

History

The GP needs to consider whether this is an acute pain, an acute exacerbation of a chronic pain or a new illness in a patient with chronic pelvic pain. It is useful to ask the woman to map out the pain and describe its associated features. They may need to keep a pain diary for two-to-three menstrual cycles. There is an excellent pain diary available to download from the National Prescribing Service Ltd at http://www.nps.org.au/data/assets/pdf_file/0003/88338/My-pain-diary.pdf.

Think ‘outside in’: so consider skin sensitivity, musculoskeletal problems aggravated by movement, trigger points with muscular spasm or neuralgic pain.1

Visceral pain from hollow pelvic organs, cervix, bowel and bladder is felt diffusely in the distribution T12-S4 so may be localised to the back, sacrum or down the legs and associated with autonomic nervous system symptoms such as sweating. It is not sharply defined in the cerebral sensory cortex, so pain in T12-S4 can relate to any of the pelvic hollow organs which have nocioceptors.3 GPs may recognise this as the type of pain occurring acutely in patients with cervical shock during miscarriage or occasionally coil fitting. The term cervical shock refers to the pain associated with vasovagal symptoms of sweating, tachycardia and low blood pressure, which can be associated with distension of the cervical canal in some women.

In addition, it is thought that the response of the body to visceral injury can cause sensitisation of neurones and neurotransmitters to create visceral hypersensitivity. Pain referred to the axial skeleton or muscle extremity may create a regional pain syndrome.

Pain is also modulated by mood and perception. The GP should ask about the mental health of the woman; she may have had premorbid anxiety and depression or have developed this secondary to the pain. Pain may be somatisation of distress due to depression or anxiety and it may be an avoidant response to painful sex. Even in older age women stories of sexual abuse affecting attitudes to intimacy are not rare.

After active listening, closed questions can identify system problems and exclude cancer in the older woman. They should cover urinary symptoms, bowels and bloating,1,4 diet, recent travel, relationship of the pain to changes in medication use and misuse, and family history of cancers. GPs should seek permission from the patient to ask about intermenstrual bleeding (IMB), postcoital bleeding (PCB), postmenopausal bleeding (PMB), vaginal discharge, sexual activity, dyspareunia and should check cervical cytology results.

Examination

It can be useful to think ‘outside in’: temperature, skin, trigger points, muscles, skeleton and pain on movement. GPs should quickly assess the abdomen for lymphadenopathy, hernias and masses.

Moving inwards the GP performs as relevant, with a chaperone present, a PR, pelvic floor, PV and speculum examination to assess structures, discharge, bleeding and oestrogen deficiency. Premenopausal women require exclusion of pregnancy and infection if indicated by the history. A woman with an acute abdomen requires admission, but many patients require further investigation. A number of chronic conditions, such as irritable bowel syndrome (IBS) or bladder pain syndrome, are diagnosed after exclusion of cancer. The GP should arrange a cancer referral for a suspicious mass or abnormality.

The post-menopausal woman

Miss Jones is a 60-year-old shop worker who attends her GP with a 10-week history of diffuse colicky pelvic pain that has deteriorated in the last week, waking her at night and radiating to her back. Her bowels are usually open once a day and now her bowels are open twice each morning. There is no relevant past medical history.

Investigations may include full blood count, c-reactive protein test, erythrocyte sedimentation rate, urea and electrolyte test, liver function test, CA125, anaemia from occult bowel blood loss, which although not specific, may be helpful. Investigations relate to the age of the woman and so prevalence of disease. In the case of the 60-year-old lady, she is postmenopausal and at a higher risk of cancer, triggering the synthesis of a number of cancer guidelines by NICE and the recent suspected cancer guidance, which integrates this information by type of cancer and by symptoms.5

NICE recommends that if a woman in this age group has symptoms of new onset IBS then the GP should exclude coeliac disease, colorectal cancer and ovarian cancer by checking for coeliac antibodies, CA125 and by arranging a faecal occult blood test.6

Ovarian cancer may present as a mass or abdominal distension and discomfort. Also, new onset IBS in the over 50s and urinary urgency or frequency are an indication for CA125. If this is equal or above 35iu/ml the GP should arranges an urgent USS. If there is any USS abnormality the patient has a two week wait referral to gynaecology outpatient clinic.7

In a patient with symptoms of raised CA125 and any abnormality on the USS, one in 26 women referred to gynaecology outpatient clinic on a two week wait referral will have ovarian cancer.7 All women with chronic pelvic pain and post-menopausal bleeding and post-coital bleeding should be referred to exclude endometrial and cervical cancers. Other tests to consider, less commonly, are fasting sugar or HbA1c, faeces C+S and thyroid function test.

Woman with chronic pelvic pain and microscopic or macroscopic haematuria in the absence of urinary infection, or if haematuria persists after UTI therapy, should be referred for investigation of cancer.

Recurrent bladder symptoms without infection may unusually be a presentation of bladder cancer.4 Consider recurrent urinary infections and dipstick the urine in surgery and send for MSU. Negative urinary symptoms with negative blood, nitrite and WCC on urine dipstick makes a urinary tract infection (UTI) unlikely.8 Sterile pyuria on MSU may rarely be TB or chlamydia. Although vaginal infections and STIs are unusual in postmenopausal women, vaginal discharge requires patient or doctor taken vulvovaginal swabs.9,10

Outcome of postmenopausal pelvic pain case This lady had very severe pain; examination and investigation in primary care as above was negative and she was referred to gastroenterology on a 2WW at review because of the minor change in bowel habit. She had a colonoscopy that diagnosed mild diverticulitis. Her symptoms settled spontaneously over another three-four months.

The premenopausal woman

Mrs XX is 20-years-old and in a bullying relationship. She attends with anxiety and requests medication. During the consultation she asks the GP about her lower colicky abdominal pain, which has occurred daily over the last four months and she has pain on sex. She always has some white vaginal discharge and is amenorrhoeic on depo-provera.

The pre-menopausal woman is more likely to have constipation and IBS. They may, however, present with inflammatory bowel disease (IBD); one third of patients with Crohn’s disease are under 21-years-old 11 and the most common IBD is ulcerative colitis, which peaks at 15-25 years old and again at 55-65 years old,  most commonly presenting with proctitis.12 The use of calprotectin is not widespread in general practice but this faecal material is produced in response to inflammation (and also tumours). Its detection in a young person at low risk of bowel cancer may be due to IBD. Its application is its negative predictive value so, in a young patient with IBS that is not responding well to therapy, a negative test may prevent inappropriate referral for colonoscopy.13 Sensitivity and specificity of low calprotectin for IBS is 80%.

Younger women are also more likely to have chronic pelvic inflammatory disease and swabs are of more significance in this age group. Exclusion of pregnancy, including ectopic pregnancy, is important.

Actinomycosis may present with chronic pain due to intrabdominal abscess formation and is difficult to diagnose. Abdominal pain, high CRP and high white cell count would be pointers to the diagnosis. It is more common in women with a copper-coil in situ.

The prevalence of endometriosis is not accurately known but should be considered in young women with hormonally driven pelvic pain.1 Characteristically, the pain is worse for a number of days before the menses, severe dysmenorrhoea and there may be dyspareunia. However, a number of patients with endometriosis have non-cyclical pain.

There are few positive discriminators for the GP and the woman may suffer subfertility and a delay in diagnosis. Transvaginal USS may detect disease but the gold standard diagnostic is laparoscopy.14 Adhesions due to endometriosis, previous surgery or pelvic inflammatory disease may cause chronic pain due to organ distension.1

Outcome of premenopausal pelvic pain case This patient had cervicitis on examination and the doctor had taken swabs whilst inspecting the cervix which revealed chlamydia. She had a low fibre diet and never ate breakfast. Her discharge cleared and pain improved after explanation, dietary advice and azithromycin for her chlamydia, but the cervical appearance persisted and she was referred to colposcopy clinic on a 2WW where an ectropion was diagnosed and treated by cryotherapy. She improved her diet and felt her pain improved considerably, recognising that tension was part of the problem.

Summary

Given that sexual abuse, anxiety and depression are common, it is very difficult for GPs and patients to co-decide whether pelvic pain is organic, psychosomatic or consists of a number of conditions. GPs may decide to refer patients, due to patient wishes, for a second opinion or may refer due to failure to cure. In patients with chronic pelvic pain, in whom no disease has been found, an integrated approach to physiotherapy and psychological based therapy has been shown to help1 and a number of gynaecological outpatient clinics now provide this.

For the GP it is important to explore the patient’s view of her pain and explain the rationale for examination and investigation; discuss the diagnoses under consideration, the need for investigation in the age group and offer continuity of care. Arrange a review appointment to discuss the results. If the patient is referred then a good management plan back to the GP from secondary care allows the practice to manage the patient’s condition most successfully.


References

1. The Initial Management of Chronic Pelvic Pain. Royal College of Obstetricians and Gynaecologists Guideline No 41. May 2012. Accessed October 2015 http://www.rcog.org.uk/womenshealth/clinical-guidance/initial-management-chronic-pelvicpain-green-top-41
2. Ahangari A. Pain Physician. 2014 Mar-Apr; 17(2):E141-7.
3. Cervero F. Visceral Pain. Accessed October 2015 http://www.wellcome.ac.uk/en/pain/microsite/science3.html
4. Engeler D., Baranowski A.P., Elneil S., Hughes Messelink E.J., et al European Association of Urology 2012. Accessed October 2015 http://uroweb.org/wp-content/uploads/24_Chronic_Pelvic_Pain_LR-March-23th.pdf
5. Suspected cancer: recognition and referral NICE guidelines [NG12] Published date: June 2015. Accessed October 2015: http://www.nice.org.uk/guidance/ng12
6. Irritable Bowel Syndrome cg 61. Feb 2008. Accessed October 2015 http://www.nice.org.uk/guidance
7. The Recognition and Initial Management of Ovarian Cancer cg 122. Nov 2011. Accessed October 2015 http://www.nice.org.uk/guidance/cg122/evidence/full-guideline-181688797
8. St John A., Boyd J.C., Lowes A.J., and Price C.P. Am J Clin Pathol. Accessed October 2015 http://ajcp.ascpjournals.org/content/126/3/428.full.pdf
9. Schoeman S.A., Stewart C., Booth R., Smith S. et al. BMJ. 12 Dec 2012. 345:e8013
10. Stewart C.M.W., Schoeman S.A., Booth R.A., Smith S.D. BMJ. 12 Dec 2012.345:e8107
11. Crohn’s disease: Management in adults, children and young people. NICE CG 152 October 2012. Accessed October 2015 https://www.nice.org.uk/guidance/cg152
12. Ulcerative colitis: management in adults, children and young people CG166 June 2013 NICE. Accessed October 2015 https://www.nice.org.uk/guidance/CG166
13. Faecal calprotectin diagnostic tests for inflammatory disease of the bowel diagnostics guidance NICE October 2013 DG11. Accessed October 2015 https://www.nice.org.uk/guidance/dg11
14. Magowan B.A., Owen P., Thomson A., Clinical Obstetrics and Gynaecology CH12. 3rd Ed 2014 Elsevier