Would orchitis (inflammation of the testis) be visible on an ultrasound in a patient with sudden testicular atrophy, low testosterone levels, and elevated Follicle-Stimulating Hormone (FSH) levels, but no apparent inflammation?

Orchitis Typically Shows on Ultrasound, But Your Clinical Picture Suggests Primary Testicular Failure, Not Active Orchitis

Your presentation of sudden testicular atrophy with elevated FSH and low testosterone indicates primary testicular failure (non-obstructive azoospermia), not active orchitis, and ultrasound would not show inflammatory changes in this scenario. 1

Understanding What Ultrasound Shows in Orchitis vs. Testicular Atrophy

Acute Orchitis on Ultrasound

When orchitis is actively present, ultrasound demonstrates characteristic inflammatory findings:

• Acute orchitis shows heterogeneous hypoechogenicity, testicular enlargement, and increased vascularity on color Doppler during the active inflammatory phase 2
• The inflamed testis appears swollen with altered blood flow patterns that are readily visible on duplex Doppler imaging 3, 4

Chronic/Resolved Orchitis Leading to Atrophy

Your situation appears different—you have testicular atrophy without current inflammation:

• After orchitis resolves (typically 25-230 days post-infection), ultrasound shows testicular atrophy characterized by decreased volume, heterogeneous hypoechogenicity with multiple hyperechoic islands, oblong shape, and decreased vascularity—not active inflammation 2
• The atrophic testis becomes 23-55% smaller in volume compared to the contralateral testis 2
• Testicular atrophy with elevated FSH >7.6 IU/L indicates spermatogenic failure (non-obstructive azoospermia), which is the end result of testicular damage, not ongoing orchitis 1

Your Clinical Picture: Primary Testicular Failure

Your constellation of findings points to established testicular damage rather than active inflammation:

• Elevated FSH with testicular atrophy indicates primary testicular failure where the pituitary is attempting to compensate for non-functioning testicular tissue 1
• Low testosterone with atrophic testes confirms impaired testicular endocrine function 5
• The absence of clinical inflammation (pain, swelling, erythema) makes active orchitis extremely unlikely 6

What Ultrasound Would Show in Your Case

Ultrasound in your situation would demonstrate testicular atrophy findings (decreased volume, altered echogenicity, reduced vascularity) rather than inflammatory changes 3, 7, 2:

• Testicular volume <12 mL defines atrophy 7
• Heterogeneous echotexture with possible hyperechoic islands 2
• Decreased or normal vascularity on color Doppler—not the increased flow seen in acute orchitis 2
• No testicular enlargement or edema 2

Critical Distinction: Asymptomatic Chronic Orchitis

There is one important caveat to consider:

• Asymptomatic chronic orchitis can occur without clinical symptoms and is only detectable on testicular biopsy, not ultrasound 8
• Focal lymphocytic infiltrates correlate with spermatogenic damage but are not visible on imaging 8
• However, this represents chronic subclinical inflammation contributing to infertility, not acute orchitis that would show on ultrasound 8

Recommended Next Steps

Given your presentation, you need comprehensive evaluation for male infertility with primary testicular failure 1:

• Karyotype testing is recommended for males with primary infertility, elevated FSH, and testicular atrophy to rule out Klinefelter syndrome (47,XXY) or other chromosomal abnormalities 1
• Semen analysis to document azoospermia or severe oligozoospermia 1
• Testicular ultrasound should still be performed to document atrophy, rule out testicular masses (as atrophic testes have 11.9-fold higher cancer risk), and assess for suspicious findings like hypoechoic masses or macrocalcifications 3, 7
• Y-chromosome microdeletion testing if azoospermia or severe oligozoospermia (<5 million/mL) is confirmed 1

Common Pitfalls to Avoid

• Do not assume active orchitis based solely on hormonal abnormalities—elevated FSH with atrophy indicates established testicular failure, not ongoing inflammation 1
• Do not delay ultrasound evaluation, as testicular atrophy increases cancer risk and requires documentation 7
• Do not confuse the ultrasound findings of post-orchitis atrophy (heterogeneous echogenicity, decreased size) with active inflammatory changes (enlargement, increased vascularity) 2
• Recognize that most chronic orchitis is asymptomatic and not detectable by ultrasound, only by histopathology 8