What is the diagnosis and treatment for a female patient of reproductive age presenting with back pain, pelvic pain, groin pain, nausea, and bloating?

Diagnosis and Management of Back Pain, Pelvic Pain, Groin Pain, Nausea, and Bloating in Reproductive-Age Women

Immediate Diagnostic Approach

Obtain a β-hCG test immediately in all reproductive-age women before any imaging to rule out pregnancy-related causes, followed by transvaginal ultrasound as the first-line imaging modality for suspected gynecological etiologies. 1, 2

Initial Workup

• Pregnancy testing is mandatory before proceeding with any diagnostic imaging to avoid missing ectopic pregnancy and to prevent inappropriate radiation exposure 1, 2
• Assess for emergency red flags: fever, vaginal bleeding, hemodynamic instability, which require immediate intervention 2
• Determine if symptoms are cyclic or hormonal in nature, as this suggests endometriosis or other gynecological causes 3

If β-hCG is Positive

• Perform transvaginal AND transabdominal ultrasound immediately to evaluate for intrauterine pregnancy, ectopic pregnancy, or pregnancy complications 1, 2
• An adnexal mass without intrauterine pregnancy has a positive likelihood ratio of 111 for ectopic pregnancy 2
• Endometrial thickness <8mm virtually excludes normal intrauterine pregnancy; ≥25mm virtually excludes ectopic pregnancy 2
• If ectopic pregnancy is confirmed, immediate obstetric consultation is required for methotrexate versus surgical management 2

If β-hCG is Negative

• Proceed with transvaginal ultrasound with Doppler imaging as first-line imaging for suspected gynecological causes 1, 2
• Ultrasound has 93% sensitivity and 98% specificity for tubo-ovarian abscess, and 98% sensitivity and 100% specificity for rectosigmoid endometriosis 2
• Combined transabdominal and transvaginal approach provides both anatomic overview and superior spatial resolution 1

Differential Diagnosis by System

Gynecological Causes (Most Likely Given Symptom Constellation)

Pelvic Inflammatory Disease (PID)

• Initiate empiric broad-spectrum antibiotics immediately if minimum criteria are met (uterine + adnexal + cervical motion tenderness), even before culture results 2
• Do not require multiple criteria before treating—requiring two or more findings reduces sensitivity and misses cases that can cause permanent reproductive damage 2
• Coverage must include N. gonorrhoeae, C. trachomatis, gram-negative facultative bacteria, anaerobes, and streptococci 2
• Ultrasound may demonstrate tubal wall thickening, pyosalpinx, or tubo-ovarian abscess 4, 2
• Obtain cervical cultures for gonorrhea/chlamydia to guide partner treatment, but do not delay antibiotics 2

Endometriosis

• Consider strongly if symptoms are cyclic or hormonal in nature, particularly if associated with severe recurring pelvic, lower back, and abdominal pain 3, 5
• This estrogen-dependent condition can cause chronic pain and may present with back pain radiating to the pelvis 5, 3
• Ultrasound has 98% sensitivity and 100% specificity for rectosigmoid endometriosis 2
• Referral for diagnostic laparoscopy is indicated in severe cases 6

Ovarian Pathology

• Ovarian cysts, ovarian torsion, and ovarian neoplasms must be considered in the differential 4, 5
• Urgent surgical consultation is required if ultrasound shows an enlarged ovary with decreased/absent Doppler flow, suggesting ovarian torsion 2
• Ovarian cysts account for approximately one-third of gynecologic pain cases 5

Pelvic Venous Disorders (Pelvic Congestion Syndrome)

• Characterized by engorged periuterine and periovarian veins (≥8mm), low-velocity flow, and altered flow with Valsalva maneuver 1, 5
• Color and spectral Doppler evaluation can document retrograde (caudal) flow of ovarian veins 1
• Many women with pelvic venous disorders have morphologic findings of polycystic ovarian syndrome 1

Uterine Fibroids and Adenomyosis

• Both are common causes of chronic pelvic pain and bloating 5, 7
• Readily identified on transvaginal ultrasound 7

Non-Gynecological Causes

Gastrointestinal Etiologies

• If ultrasound is inconclusive or non-gynecological etiology is suspected, CT abdomen and pelvis with IV contrast is the preferred imaging 1, 2
• Appendicitis remains the most common surgical emergency with CT sensitivity of 95% and specificity of 94% 4
• Right colonic diverticulitis accounts for 8% of right lower quadrant pain cases 4
• Inflammatory bowel disease can cause chronic pelvic pain with similar symptoms 5

Urological Causes

• Ureteral calculi cause colicky pain radiating to the pelvis and groin 4
• Interstitial cystitis presents with chronic pelvic pain, urinary urgency, frequency, and nocturia—often misattributed to gynecological causes 8
• Bladder-origin pelvic pain should be considered in all women presenting with these symptoms 8

Musculoskeletal Causes

• Do not routinely obtain imaging for nonspecific low back pain unless severe or progressive neurologic deficits are present or serious underlying conditions are suspected 1
• Pelvic myofascial pain and pelvic girdle pain can mimic gynecological pathology 5
• Endometriosis can affect retroperitoneal spinal and neural elements, causing cyclic sciatica and back pain 3

Imaging Algorithm

First-Line Imaging

• Transvaginal ultrasound with Doppler for suspected gynecological causes (no radiation, superior sensitivity for ovarian pathology) 1, 2
• Do not use CT as first-line for gynecological causes—ultrasound has equivalent or superior diagnostic accuracy without radiation exposure 2

Second-Line Imaging

• CT abdomen and pelvis with IV contrast if ultrasound is inconclusive or non-gynecological etiology is suspected 1, 2
• CT has 98% overall accuracy for diverticulitis and high diagnostic yield for appendicitis and alternative diagnoses 1, 4
• Avoid routine imaging in young women due to significant gonadal radiation exposure—a single lumbar spine radiograph (2 views) equals daily chest radiographs for more than 1 year 1

Advanced Imaging

• MRI abdomen and pelvis without IV contrast may be appropriate if index of suspicion is high for appendicitis or bowel abnormalities, especially in pregnancy 1
• MRI has 86-94% sensitivity and 88-92% specificity for diverticulitis 1
• Contrast-enhanced CT or MRI can demonstrate engorged periuterine and periovarian veins in pelvic venous disorders 1

Treatment Approach

Gynecological Management

• For suspected PID, start empiric antibiotics immediately—do not wait for culture results 2
• For endometriosis, potentially beneficial medications include depot medroxyprogesterone, gabapentin, NSAIDs, and GnRH agonists with add-back hormone therapy 6
• Pelvic floor physical therapy may be helpful for chronic pelvic pain 6
• Hysterectomy should be considered only as a last resort if pain seems to be of uterine origin, with significant improvement occurring in only about one-half of cases 6

Non-Gynecological Management

• For nonspecific low back pain, reevaluate patients with persistent, unimproved symptoms after 1 month 1
• Prompt work-up with MRI or CT is required if severe or progressive neurologic deficits are present or serious underlying conditions are suspected (vertebral infection, cauda equina syndrome, cancer with spinal cord compression) 1

Critical Pitfalls to Avoid

• Do not dismiss mild or atypical symptoms—many PID cases present with nonspecific symptoms like abnormal bleeding or dyspareunia 2
• Do not forget pregnancy testing—failure to obtain β-hCG can lead to missed ectopic pregnancy or inappropriate radiation exposure 1, 2
• Do not assume gynecologic origin without considering other systems—chronic abdominal pain has a broad differential including gastrointestinal, urologic, and musculoskeletal causes 5
• Do not overlook interstitial cystitis—bladder-origin pelvic pain is frequently misattributed to other causes of chronic pelvic pain 8
• Consider endometriosis in any female patient with cyclic back pain—ask whether there is a significant hormonal cyclic nature to symptoms to prevent unnecessary spinal procedures 3