Sporotrichosis is a fungal infection that can occur in cutaneous or extracutaneous forms. While the skin infection is is mostly benign, the severe forms of the infection when disseminated to other organs could be debilitating and even life threatening especially in immunocompromised individuals.
There are two manifestations of sporotrichosis, cutaneous and extracutaneous. The former is subdivided into lymphocutaneous, fixed, and disseminated. The presentation of these forms is as follows:
Lymphocutaneous: The most common form of the infection is lymphocutaneous sporotrichosis. Primary lesions can appear at site of initial contact with S. schenckii <1 month to 3 months after exposure. This occurs on distal extremities, usually a hand and arm are involved. However, it can be seen on other parts of the body. The primary lesion is usually a small, firm, nontender, pinkish purplish papule. Sometimes, it presents as a growing subcutaneous nodule that necroses and ulcerates. A few weeks after the primary lesion appears, palpable, mobile lymph nodes appear. Lymph node involvement occurs in 60% of cases. These lesions form along the lymphatic tracks of the affected extremity and are characteristic of sporotrichosis. Most infections affect the skin and it is rare that it spreads to bone, joints, brain or other organs. Patients remain afebrile and well during this process. Patients fail antibiotic therapy  .
If not treated, the skin on which the lesions develop, becomes erythematous and necrotic. This is followed by the formation of an abscess, ulcer and possibly the development of a bacterial superinfection. If the latter occurs, systemic signs of infection may be present or absent. If not treated, superinfection can causes sepsis and illness.
Fixed cutaneous: In the fixed cutaneous form, a painless erythematous plaque appears. Unlike the presentation in lymphocutaneous sporotrichosis, this type result in the formation of other lesions. This plaque may ulcerate or become verrucous. If a wound fails to heal, the diagnosis of fixed cutaneous sporotrichosis should be suspected .
Disseminated: If sporotrichosis spreads to other organs, the signs and symptoms depend on its effects on that particular organ. Also uncommon is the dissemination of the infection to bones, brain, liver, spleen, GI tract, kidneys or eyes. In immunocompromised patients, infection can be spread throughout cutaneously and viscerally  . This, however, is uncommon.
While this is very rare, pneumonia can occur as a result of S. schenckii spore inhalation. This presents in patients with preexisting lung disease such as COPD. The symptoms include cough and typical symptoms of pneumonia . On radiograph, the appearance of cavitary lesions is similar to the findings in tuberculosis and histoplasmosis.
Also rare is the presentation of osteoarticular arthritis which is a form of chronic arthritis. The clinical picture is similar to other types of arthritis.
Entire Body System
The lesions were more frequent on the eyelids (n 53 [82%]), followed by the lacrimal gland (n 5), conjunctiva (n 4), and eyebrows (n 3). The lymphocutaneous clinical form (54%) was the most frequent. [ncbi.nlm.nih.gov]
Although rare, ophthalmologists should be aware of this entity during examination of patients with intractable conjunctival injection. [ncbi.nlm.nih.gov]
Serology used in this case was an invaluable tool for the diagnosis of sporotrichosis arthritis lacking skin lesions. [ncbi.nlm.nih.gov]
Fixed sporotrichosis is isolated to the skin lesions mentioned above. Disseminated sporotrichosis begins as skin lesions and will progress into a systemic disease. [aocd.org]
We report a case of a farmer who presented with a solitary subcutaneous nodule initially diagnosed as a soft tissue tumour. [ncbi.nlm.nih.gov]
nodules along the course of the lymphatics in two to three weeks. [jamanetwork.com]
Sometimes, it presents as a growing subcutaneous nodule that necroses and ulcerates. A few weeks after the primary lesion appears, palpable, mobile lymph nodes appear. Lymph node involvement occurs in 60% of cases. [symptoma.com]
He developed multiple subcutaneous nodules and an ulcer over the right thigh even after 6 weeks of treatment. Thus, saturated solution of potassium iodide (SSKI) was added with complete clearance of the lesions in 10 weeks. [e-ijd.org]
nodules that progress proximally along lymphatic channels (lymphocutaneous sporotrichosis). [emedicine.com]
ulcers that do not go away. [nlm.nih.gov]
The incidence of adverse events was similar for both groups (64.7%): predominantly metallic taste (44%), followed by mild gastrointestinal intolerance and acneiform eruption (10.7% each). [ncbi.nlm.nih.gov]
It is important to do a thorough workup to accurately diagnose and treat this infection.
- Culture: Obtain a sample from sputum, pus, tissue biopsy, or cerebrospinal fluid (CSF) to isolate S. schenckii, which will provides diagnosis. It is important to confirm this diagnosis as Mycobacterium tuberculi, Nocardia and other organisms may present with a similar clinical picture.
- Serology is not available.
- Antibody tests are available, but not always reliable .
- Staining is difficult and and rarely are S. schenckii seen.
- CSF antibody: Serum antibody ratio can suggest sporotrchotic meningitis .
- PCR not available for use
- Arthrocentesis can be performed to retrieve synovial fluid used for culture.
- Imaging: Chest X-ray and CT ahow no definitive characteristic to confirm the diagnosis.
Cavitary lesions observed in three of the patients were treated by pulmonary resection and chemotherapy with amphotericin B and iodides. [nejm.org]
On radiograph, the appearance of cavitary lesions is similar to the findings in tuberculosis and histoplasmosis. Also rare is the presentation of osteoarticular arthritis which is a form of chronic arthritis. [symptoma.com]
CT scan revealed single thin-walled cavitary lesion in lower-left lung [Figure 1]. Therefore, three consecutive sputum samples were sent for AFB microscopy and fungal microscopy and culture. [jlponline.org]
Surgery may be indicated for relapsing or refractory/pulmonary cavitary lesions or for mediastinal mass lesions although it has not been demonstrated that this helps prevent mediastinal fibrosis. [jac.oxfordjournals.org]
Persistent chest X-ray abnormalities were found in 13% and mycological cure was observed in 87% within the first month of treatment. [jac.oxfordjournals.org]
Chest X-Ray Abnormal
Persistent chest X-ray abnormalities were found in 13% and mycological cure was observed in 87% within the first month of treatment. [jac.oxfordjournals.org]
Generally, azole antifungal drugs are the drugs of choice for cutaneous or lymphocutaneous sporotrichosis .
Cutaneous or lympocutaneous sporotrichosis: Itraconazole (oral) 200mg daily. Continue 2-4 weeks after resolution of lesions. Treatment may span 3 to 6 months. Supersaturated potassium iodide (SSKI) could be used alternatively.
Pulmonary sporotrichosis: If mild: Itraconazole (oral): 200mg twice daily for one year or more. If severe: Amphpotericin B: 3 to 5 mg/kg IV once/day then switch to itraconazole for 12 months.
Osteoarticular sporotrichosis: Itraconazole (oral) 200mg twice daily for one year or more.
Disseminated sporotrichosis: Amphotericin B induction 5 mg/kg/day, followed by itraconazole as step down therapy. Itraconazole (oral) 200mg twice daily for one year or more. In AIDS patients, lifelong maintenance treatment with itraconazole could be beneficial.
The prognosis of sporotrichosis depends on the form.
- Cutaneous or lympocutaneous sporotrichosis: Successful recovery with itraconazole. Spontaneous recovery has been seen in cutaneous sporotrichosis.
- Pulmonary sporotrichosis: Can cause deterioration in patients with underlying COPD. According to the evidence, patients respond well to treatment.
- Osteoarticular sporotrichosis: Could be debilitating and disabling if not treated. Chronic forms can seriously compromise the joint. Itraconazole therapy yields a good response, but relapses occur.
- Disseminated sporotrichosis: Good response with amphotericin B. This is life-threatening in immunocompromised patients and has been linked to serious complications. AIDS patients with disseminated sporotrichosis may require long term therapy with itraconazole.
The etiology of sporotrichosis derives from the fungus S. schenckii. It is commonly found on rose or barberry bushes in addition to sphagnum moss and mulches. Individuals at the highest risk are gardeners, farmers, landscapers, timber workers and other similar laborers. Exposure occurs with minor skin cuts and abrasions. S. schenckii may penetrate cutaneous and subcutaneous tissue as well as lymphatics . Less commonly, S. Schenckii is inhaled leading to pneumonia. Also rare is the dissemination to other organs.
S. schenckii, a dimorphic fungus, is found worldwide but the incidence is unknown. Certain areas such the highlands of Peru are hyperendemic, where the incidence is 1 per 1000 population . In the United states, there are 200-250 cases yearly . Sporotrichosis is found in males more than females, but this is likely due to higher exposures with respect to occupation.
Sporotrichosis in developed countries is more common in adults while it is more common in children in hyperendemic regions and tropical areas. Outbreaks have occurred in the United, States, Western Australia, and Brazil. New susceptible populations are veterinarians and cat owners.
Infection with S. schenckii is acquired by inoculation through skin exposure with contaminated matter such as plants or other plant materials. Humans cannot transmit the disease to other humans. Zoonotic transmission is possible as animals can spread it to humans through bites or scratches. Within <1 month to 3 months after inoculation, red, necrotic, nodular papules appear. These lesions are pus forming granulomas infiltrated with histiocytes and giant cells. In addition, neutrophils, lymphocytes, plasma cells and other immunomodulators are also present. The infection spreads in the lymphatics and forms a trail of lesions in 60% of cases.
Direct extension or hematogenous dissemination of the infection may occur. The latter is not common but can develop, specifically, in immunocompromised patients. Immunocompromised patients may experience meningitis and widely disseminated infection.
Extracutaneous infection can manifest in bones, joints, tendon sheaths, and bursae. Osteoarticular sporotrichosis may occur if the joint is involved. It can develop into chronic osteomyelitis or arthritis. The clinical picture resembles that of rheumatoid arthritis and inflammatory arthritis. This could lead to joint destruction if not treated appropriately.
Prevention focuses on reducing the risk for exposure. Protective clothing, gloves, long sleeves, and boots can help prevent infection when gardening, landscaping, farming, etc. Also this is advised for individuals handling pine seedlings, sphagnum moss, and other possibly contaminated matter. Exercise caution with handling of animals with cuts since they can be a source of transmission. Another recommendation is to be aware and cautious of cuts or abrasions on the skin to avoid infection in general.
Sporotrichosis is caused by the dimorphic fungus Sporothrix schenckii, which is found worldwide especially in tropical and subtropical regions. Sporotrichosis affects gardeners, farmers, and workers in other similar occupations. Infection occurs when an abrasion or cut in the skin comes into to contact with the fungus in soils, plants, and other matter contaminated with S. schenckii.
Sporotrichosis comes in different forms. The clinical manifestations vary from one patient to another. When the skin nodules form pus that travels in the lymphatic system, this is called lymphocutaneous sporotrichosis. Additionally, there is the extracutaneous form which may affect the lung or joints. The disseminated form spreads throughout the body and can increase mortality in immunocompromised hosts.
The diagnosis of this infection is made accurately by considering the occupation and hobbies of the patient in addition to acknowledging the geographical location in which the individual resides. The treatment is similar for most of the forms which elicits good responses.
Sporotrichosis is an infection caused by a fungus called Sporothrix schenckii. This infection is found in gardeners, farmers, landscaper, handlers of plants, etc. It occurs in rose and barberry bushes in addition to sphagnum moss and mulches. While it is found throughout the world, tropical zones are abundant with this fungus. The infection comes in different forms.
The most common form is known as lymphocutaneous sporotrichosis. This happens when a wound on the skin comes in contact with material contaminated with the fungus. Usually this occurs on the hand. A skin lesion forms in about 1 to 3 months after contact. A small, nonpainful pinkish purplish bump forms and eventually becomes filled with pus. In the next weeks this travels through the lymph channels. Bumps form along the way. This is treated with an antifungal called itraconazole for 3 to 6 months.
Another type is called disseminated sporothrichosis. Although not common, this infection can spread and infect joints, bones, and other body parts as well. There is also a form called fixed cutaneous sporotrichosis but this does not spread. Pneumonia can happen if the spores of the fungus are inhaled. Again this is not common.
Sporotrichosis is diagnosed by a sample of fluid from the skin lesion or fluid from other infected parts. The infection in general is typically successfully treated with antifungals of the “azole” family. Preventative measures should be taken. For individuals working in gardening, landscaping, farming, and other similar occupations or hobbies, it is important to wear protective clothing, gloves, long sleeves, and boots. Also caution should be exercised with cuts and infections to avoid all infections in general. Also be careful with animals that have cuts and abrasions. This infection can be spread from animal to person. However, it does not spread from human to human.
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