Groin Swellings
Differential Diagnosis
Common Diagnoses
- Sebaceous Cyst
- Palpable Lymph Nodes (LNs): ‘Normal’ or Secondary to an Infection
- Inguinal Hernia
- Femoral Hernia
- Saphena Varix
Occasional Diagnoses
- Retractile Testicle
- Abscess (Local)
- Metastatic Tumour (Usually as Skin-Fixed Lymphadenopathy)
- Hydrocele of Spermatic Cord
- Low Appendix Mass, Pelvic/Inguinal Tumour
- Lipoma
Rare Diagnoses
- Abscess (Psoas)
- Lymphoma
- Femoral Artery Aneurysm
- Neurofibroma
- Undescended or Ectopic Testis
Ready Reckoner
Key distinguishing features of the most common diagnoses
| Sebaceous Cyst | LNs | Inguinal Hernia | Femoral Hernia | Saphena Varix | |
|---|---|---|---|---|---|
| Reducible | No | No | Possible | Possible | Yes |
| Cough Impulse | No | No | Yes | Possible | Yes |
| Palpable Thrill on Valsalva Manoeuvre | No | No | No | No | Yes |
| Fixed to Skin | Yes | No | No | No | No |
| Originates Above and Medial to Pubic Tubercle | Possible | Possible | Yes | No | No |
Possible Investigations
Likely:None
Possible:FBC, ESR/CRP, GUM screen.
Small Print:Pelvic ultrasound.
- FBC and ESR/CRP useful if diffuse lymphadenopathy found, especially if no evidence of local cause or other significantly enlarged nodes found. Hb may be reduced and ESR/ CRP elevated in malignancy; WCC and ESR/CRP elevated in abscess, infection and blood dyscrasias
- Urethral, vaginal or endocervical swabs indicated if any associated discharge and/or suspicion of STD.
- Pelvic ultrasound useful if pelvic mass suspected.
Top Tips
- A large saphena varix can look very much like a small hernia. Try the Valsalva test and look for evidence of varicose veins.
- If the cause is local lymphadenopathy, look for local infective causes and don’t forget to consider STDs
- Don’t be surprised to find no abnormality – normal groin nodes in a slim person, and a normally retractile testis can cause great anxiety in patients and parents.
- If the history suggests a hernia, but nothing is obvious on examination, get the patient to raise the intra-abdominal pressure with a vigorous cough or by raising the legs straight up while lying on the couch – and remember to examine the patient standing up, too.
Red Flags
- Femoral herniae (commoner in women) are at high risk of strangulation, so always refer
- Undescended testis in the adult carries a high risk of malignancy. If the testis is not descended by the age of six months, then operative intervention is indicated. Bilateral undescended testes need urgent referral
- If lymphadenopathy is the cause, look elsewhere for abnormal lymph nodes and investigate or refer if any are found. Hard, skin-fixed nodes suggest metastatic malignancy – refer urgently.
- An acutely painful and irreducible groin lump suggests a strangulated or incarcerated hernia. If in any doubt, refer for urgent surgical assessment.