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Coccidioidomycosis

What is coccidioidomycosis?

Coccidioidomycosis is a fungus infection It mainly affects the lungs and respiratory tract. In rare cases, it can spread to other parts of the body.

Coccidioidomycosis is also known as the San Joaquin Valley fever (or just valley fever) or desert rheumatism. It occurs in the western United States and parts of Mexico and Central and South America.

What Causes Coccidioidomycosis?

Coccidioidomycosis is caused by two distinct species of soil fungus Coccidiodies, Coccidioides immitis and Coccidioides posadaii.

Infection occurs through:

  • Inhalation spore during outdoor activities (most common)
  • Puncture wounds with infected objects.
  • Organ transplant or sexual transmission from an infected individual (rare).

What are the signs and symptoms of coccidioidomycosis?

In 65% of cases, patients with coccidioidomycosis are asymptomatic.

Patients with mild or self-limited infections will have:

  • Mild fever with chills and night sweats.
  • Fatigue
  • Pain (headaches, sore throat, chest pain)
  • A cough, with possible sputum production and hemoptysis
  • Swelling of the lower limb / foot
  • Loss of appetite
  • Rattling of the chest, sometimes opaque from percussion over the lung fields.
  • Arthralgias.

Primary cutaneous coccidioidomycosis is very rare and arises from a inoculation injury. It comes as a indurated nodule and is one of the causes of sporotrichoid spread associated with lymphadenopathy.

What is it disseminated coccidioidomycosis and what are the signs and symptoms?

Disseminated coccidioidomycosis refers to the spread of lung infection to other organs.

This progress can be rapid and involve soft tissues, joints, central nervous system, endocrine glands, eyes, liver, kidneys, peritoneal cavity and, most seriously, the meninges (lining around the brain). Left untreated, coccidioid infections of the meninges are almost always fatal.

Patients with disseminated coccidioidomycosis may present:

  • Altered mental state
  • Lymph node extension
  • Neck stiffness
  • Swelling / stiffness of the joints.
  • Sensitivity to light
  • Unexplained weight loss

What are the skin characteristics of disseminated coccidioidomycosis?

The skin signs are variable and can include single or multiple infections. papules, nodules, pustulesabscesses ulcers and scars

Reactive manifestations can include:

  • Erythema knotty (common, arising three weeks after pulmonary infection)
  • Erythema multiforme
  • A exanthema or toxic erythema (in 10 to 50% of patients)
  • Acute febrile neutrophilic skin disease (rare)
  • Interstitial granulomatous dermatitis (rare).

What are the risk factors for coccidioidomycosis?

Risk factors for coccidioidomycosis include:

  • Travel to endemic areas (the southwestern United States and parts of Mexico, Central and South America).
  • Immunocompromised status (immunodeficiency, immunosuppressive drugs)
  • The pregnancy
  • Occupation. Farmers, construction workers and archaeologists are at risk.
  • Sex. Men are at higher overall risk than women, mainly for occupational reasons.
  • Race. Filipinos, Africans, Native Americans, or Hispanics with blood types A or B are considered to be at higher risk.
  • History of lymphoma, organ transplantation or treatment with tumor necrosis factor inhibitors (TNF)
  • Time of the year. Incidence it is greatest in late summer and early fall due to a combination of dry soil and wind.

How is coccidioidomycosis diagnosed?

The diagnosis of coccidioidomycosis is made through:

  • Blood tests to look for coccidioid species
  • Sputum smear (KOH microscopy)
  • Polymerase chain reaction (PCR) from an infected site
  • Isolation of organism in culture and subsequent histological and serological tests.
  • Chest x-ray

More serious cases may require additional tests, including:

  • Lung, liver, or lymph node or bone marrow biopsy
  • Spinal blow (for suspected meningeal involvement)
  • Bronchoscopy with lavage
  • Skin biopsy. This can show suppurative granulomas containing refractile double-walled spherules with endospores. See pathology of coccidioidomycosis.

How is coccidioidomycosis treated?

  • For mild, self-limited symptoms, supportive care is more common.
  • Drug therapy with fluconazole or itraconazole (for moderate cases) or posaconazole or amphotericin B (for severe cases) is standard. This treatment can continue for months or years, and in some patients, lifelong suppression will be required.