++

Key Features

+

  • • A contagious disease largely limited to tropical regions that is caused by Treponema pallidum subspecies pertenue

    • Acquired by direct nonsexual contact, usually in childhood, although it may occur at any age

++

Clinical Findings

+

  • • Characterized by granulomatous lesions of the skin, mucous membranes, and bone

    • The “mother yaw,” a painless papule that later ulcerates, appears 3–4 weeks after exposure

    • Regional lymphadenopathy is usually present

    • Secondary lesions that are raised papillomas and papules

    • – Appear 6–12 weeks later

      – Weep highly infectious material

      – Last for several months or years

    • Painful ulcerated lesions on the soles are called “crab yaws” because of the resulting gait

    • Late gummatous lesions may occur, with associated tissue destruction involving large areas of skin and subcutaneous tissues

    • Late effects of yaws may be confused with similar changes occurring in leprosy and include

    • – Bone change

      – Shortening of digits

      – Contractures

    • Central nervous system, cardiac, or other visceral involvement is rare

++

Diagnosis

+

  • • Organisms can be demonstrated in infectious lesions with darkfield microscopy or immunofluorescence but cannot be cultured in artificial media

    • Serologic tests for syphilis are positive

++

Treatment

+

  • • If untreated, may lead to chronic disability and disfigurement

    • Penicillin, 2.4 million units of benzathine penicillin G intramuscularly is generally curative in any stage of the non–sexually transmitted treponematoses

    • In cases of penicillin hypersensitivity, tetracycline, 500 mg orally four times a day for 10–14 days, is the recommended alternative

++

Content adapted from CURRENT Medical Diagnosis & Treatment 2014.

++

Key Features

+

  • • Zoonotic viral infection transmitted by the bite of the Aedes mosquito

    • Found in South America and sub-Saharan Africa (not Asia)

    • Incubation period is typically 3–6 days

    • Adults and children equally susceptible

++

Clinical Findings

+

  • • Mild form (85%)

    • – Fevers

      – Malaise

      – Retro-orbital pain

      – Nausea

      – Photophobia

      – Bradycardia

    • Severe form (15%)

    • – Begins with the same symptoms as the mild form of the disease

      – Then, after initial remission of symptoms, a toxic phase ensues with fever, bradycardia, hypotension, jaundice, delirium, hemorrhage

++

Diagnosis

+

  • • Leukopenia often but not always present

    • Abnormal liver function tests, including prolonged PT

    • Renal insufficiency with proteinuria is present, often in large quantities

    • Serologic diagnosis with rapid enzyme immunoassay

++

Treatment

+

  • • Supportive measures, including analgesia and hydration

    • No specific antiviral therapy

    • Prevention: a highly effective and safe vaccine is available and should be used when living or traveling to endemic areas

    • Prevention: mosquito control measures

++

++

Content adapted from CURRENT Medical Diagnosis & Treatment 2014.

Want access to your institution's subscription?

Sign in to your MyAccess Account while you are actively authenticated on this website via your institution (you will be able to tell by looking in the top right corner of any page – if you see your institution’s name, you are authenticated). You will then be able to access your institute’s content/subscription for 90 days from any location, after which you must repeat this process for continued access.

Ok

About MyAccess

If your institution subscribes to this resource, and you don't have a MyAccess account, please contact your library's reference desk for information on how to gain access to this resource from off-campus.

Subscription Options

AccessMedicine Full Site: One-Year Subscription

Connect to the full suite of AccessMedicine content and resources including more than 250 examination and procedural videos, patient safety modules, an extensive drug database, Q&A, Case Files, and more.

$995 USD
Buy Now

Pay Per View: Timed Access to all of AccessMedicine

24 Hour Subscription $34.95

Buy Now

48 Hour Subscription $54.95

Buy Now

Pop-up div Successfully Displayed

This div only appears when the trigger link is hovered over. Otherwise it is hidden from view.