Laboratory Studies
Laboratory tests and findings in filarial hydrocele are as follows:
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Complete blood cell count (CBC): Patients with patent filarial infection commonly have marked eosinophilia
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Serum immunoglobulins: Elevated serum levels of immunoglobulin E (IgE) and immunoglobulin G4 (IgG4) are seen with microfilarial infection
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Enzyme-linked immunoassay (ELISA): Og4C3 monoclonal antibody–based ELISA provides a quantitative measure of circulating filarial antigen (CFA)
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Hydrocele fluid examination: CFA may be detected in hydrocele fluid, [11] and microfilariae may be found on cytology
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Urine examination: Chyluria may be detected macroscopically, and microfilariae may be detected via microscopic examination of voided urine; proteinuria and hematuria may also be seen with microfilarial infection with renal involvement
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Peripheral blood examination: Microfilariae may be detected via microscopic examination of peripheral blood; microfilariae demonstrate a circadian pattern that varies by endemic region, necessitating serum sampling that coincides with periods of activity; activity may be provoked with administration of DEC
Imaging Studies
Lymphatic obstruction can be demonstrated on ultrasonography. Motile adult worms may be seen in symptomatic and subclinical filarial hydroceles. The characteristic movements of adult filarial worms are called the filarial dance sign (FDS) and are a reliable diagnostic finding. Ultrasonography may also be used to monitor response to treatment.
Staging
To guide surgical management, Capuano and Capuano have proposed a standardized clinical classification of filarial hydroceles, based on four criteria [12] :
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Type – Unilateral versus bilateral
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Side (left/right)
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Scrotal enlargement - Rated from I to VI
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Grade of burial of the penis – Rated from 0 to 4
For size of the scrotum, the rating scale is as follows:
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Stage I: Smaller than a tennis ball
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Stage II: Larger than of a tennis ball up and down; the lower pole of the scrotum does not reach halfway down the thigh (between the lower edge of the great trochanter and the upper edge of the patella)
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Stage III: The lower pole of the scrotum reaches the area between mid-thigh and the knee (upper edge of the patella
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Stage IV: The lower pole of the scrotum reaches the area between the upper edge of the patella and the lower edge of the knee (tibial tuberosity)
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Stage V: The lower pole of the scrotum reaches the area between the lower edge of the knee (tibial tuberosity) and the middle of the lower leg
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Stage VI: The lower pole of the scrotum reaches the area between mid-leg and the ankle (bi-malleolar line)
For burial of the penis, which can be assessed with the patient standing or lying down, the rating scale is as follows:
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Grade 0: No apparent burial; penis length is within normal limits
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Grade 1: Partial burial; the length of the visible part of the penis is > 2 cm
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Grade 2: More important partial burial; the length of the visible part of the penis is < 2 cm
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Grade 3: Total burial; the prepuce, or the tip of the glans penis if the patient is circumcised, is visible and flush with the surface of the scrotum
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Grade 4: Total burial; the glans penis is invisible, and the burial cannot be reduced and causes micturition problems
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Filarial infection causing enlarged pubic lymph nodes.
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Laparoscopic view of enlarged lymphatics secondary to filarial infection.
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Lymphocele of the right spermatic cord.
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Microfilaria of Wuchereria bancrofti in a peripheral blood smear.
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Unilateral left hydrocele and testicular enlargement secondary to Wuchereria bancrofti infection in a man who also was positive for microfilariae.
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Bilateral hydrocele, testicular enlargement, and inguinal lymphadenopathy secondary to Wuchereria bancrofti infection in a man who also was microfilaremic.
