Classic and contemporary imaging of coccidioidomycosis

Disseminated Coccidioidomycosis: Cutaneous, Soft Tissue, Osseous, and "Shotgun Intraparenchymal" Brain Disease

Coccidioidomycosis is a disease found in the southwestern United States and caused by inhalation of arthroconidia of Coccidioides immitis and posadasii. Although the disease is most commonly asymptomatic or respiratory, it has a propensity to disseminate to any tissue in the body with the most common being skin, bone, joints, and central nervous system. This case demonstrates the dissemination of coccidioidomycosis to several foci along with a rare form of parenchymal dissemination with an unusual neuroradiological finding.

Disseminated Coccidioidomycosis to the Gallbladder

Coccidioidomycosis is an infection caused by inhalation of arthroconidia produced by dimorphic fungi in the genus Coccidioides. Forty percent of patients will develop an influenza-like illness with symptoms suggestive of a mild and self-limited respiratory infection; however, 5% of these individuals will develop extrapulmonary disseminated disease. An immunocompromised patient presented with right upper quadrant pain, ultrasound with pericholecystic fluid, in which a percutaneous cholecystostomy contained biliary fluid that grew the fungus Coccidioides immitis. Patient was initiated on intravenous amphotericin therapy and was followed closely with postoperative bile drainage with eventual laparoscopic cholecystectomy. We present a very rare case of disseminated coccidioidomycosis to the gallbladder.

A Case of Osteomyelitis of the toe caused by Coccidioidomycosis in a 17 year-old with Diabetes Insipidus

We report a case of a 17-year-old male who presented with pain in his right first toe. His pain and swelling had worsened and x-rays of his foot revealed erosive changes of the great toe distal phalanx suggesting possible osteomyelitis. His co-morbidities were morbid obesity and diabetes insipidus. He was admitted to the hospital, blood cultures were drawn, and he was started on vancomycin for presumed bacterial osteomyelitis. He underwent incision and drainage of the fluctuant abscess of the toe, where a culture of the wound was taken. Preliminary results grew fungi. Being located in an endemic area, he was started on anti-fungal treatment for presumed disseminated coccidioidomycosis; culture was positive for Coccidiodes immitis. He also had serology positive for coccidioidomycosis titers. He had uneventful hospital stay and was discharged on long-term oral antifungal therapy.

Coccidioidomycosis Fungal Infection in the Hand Mimicking a Metacarpal Enchondroma

Coccidioidomycosis, an infection caused by the fungus Coccidioides immitis, rarely affects the hand, but we report an unusual case which mimicked the radiological appearance of an enchondroma in the metacarpal. Curettage and bone grafting in combination with long-term antifungal therapy are necessary for successful treatment of coccidioidomycosis of the hand.

Coccidioidomycosis osteomyelitis of the knee in a 23-year-old diabetic patient

Coccidioidomycosis is a pulmonary infection caused by the dimorphic fungi Coccidioides immitis and Coccidioidomycosis posadasii. This disease is endemic to the southwestern United States and has a predilection for immunocompromised patients. Diabetes mellitus has been shown to be a strong risk factor for acquiring this infection in these states. Most cases are asymptomatic or present with mild pulmonary symptoms. However, untreated pulmonary mycosis can lead to disseminated infection, most often involving meningitis, osteomyelitis, or skin and soft-tissue infections. When there is arthritis, the knee is the most common site of infection. We present a case of a 23-year-old male with longstanding, uncontrolled Type 1 diabetes mellitus who was found to have pulmonary coccidioidomycosis following diagnosis of coccidioidomycosis osteomyelitis of the knee.

Case 209: Disseminated coccidioidal spondylodiskitis

History A 46-year-old Hispanic man with a medical history of diabetes and hepatitis C and an unclear history of prior infectious disease presented to the emergency department of a community medical center in the northeastern United States with a 3-month history of back pain. The patient was originally from Mexico and had been living in the United States for approximately 1 year. Physical examination at the time of admission was noncontributory. Pertinent hematologic laboratory test results were as follows: white blood cell count, 11.2 ×10(9)/L (normal range, [4.5-11.0] ×10(9)/L); neutrophil level, 81.3% (0.81) (normal range, 38.9%-75.1% [0.39-0.75]); hemoglobin level, 7.9 g/dL (normal range, 13.5-18.0 g/dL); hematocrit level, 23.2% (0.23) (normal range, 40.0%-54.0% [0.40-0.54]); and calcium level, 8.3 mg/dL (2.07 mmol/L) (normal range, 8.4-10.4 mg/dL [2.1-2.6 mmol/L]). Protein electrophoresis revealed hypergammaglobulinemia consistent with chronic inflammation. Relevant radiologic studies included computed tomography (CT) and magnetic resonance (MR) imaging of the spine.

Coccidiomycosis infection of the patella mimicking a neoplasm - two case reports

Background

Coccidioidomycosis is an endemic fungal infection in the southwestern of United States. Most infections are asymptomatic or manifest with mild respiratory complaints. Rare cases may cause extrapulmonary or disseminated disease. We report two cases of knee involvement that presented as isolated lytic lesions of the patella mimicking neoplasms.

Case Presentation

The first case, a 27 year-old immunocompetent male had progressive left anterior knee pain for four months. The second case was a 78 year-old male had left anterior knee pain for three months. Both of them had visited general physicians without conclusive diagnosis. A low attenuation lytic lesion in the patella was demonstrated on their image studies, and the initial radiologist’s interpretation was suggestive of a primary bony neoplasm. The patients were referred for orthopaedic oncology consultation. The first case had a past episode of pulmonary coccioidomycosis 2 years prior, while the second case had no previous coccioidal infection history but lived in an endemic area, the central valley of California. Surgical biopsy was performed in both cases due to diagnostic uncertainty. Final pathologic examination revealed large thick walled spherules filled with endospores establishing the final diagnosis of extrapulmonary coccidioidomycosis.

Conclusions

Though history and laboratory findings are supportive, definitive diagnosis still depends on growth in culture or endospores identified on histology. We suggest that orthopaedic surgeons and radiologists keep in mind that chronic fungal infections can mimic osseous neoplasm by imaging.

Computed tomography for the diagnosis of infectious diseases of the chest

BACKGROUND

Pulmonary infection is a common reason for imaging of the lung in immunocompetent and immunosuppressed patients. Findings on chest radiography are nonspecific and encompass poor sensitivity. The role of computed tomography (CT) has been evolving in the diagnosis of lung infections.

OBJECTIVE

This paper reviews recent developments in the efficacy and utility of CT in the diagnosis of suspected pulmonary infections in a variety of patient populations.

METHODS

Recent published literature was reviewed to prepare this treatise on the role of CT.

CONCLUSION

Knowledge and skills at pattern recognition are crucial for the CT interpretation in lung infections. Computed tomography scan is increasingly used to increase the sensitivity of the radiologic diagnosis of thoracic infections. The greatest value of CT is when the radiograph is normal, findings are equivocal, and to differentiate infection from non-infectious disorders.

Cavitary pulmonary disease

A pulmonary cavity is a gas-filled area of the lung in the center of a nodule or area of consolidation and may be clinically observed by use of plain chest radiography or computed tomography. Cavities are present in a wide variety of infectious and noninfectious processes. This review discusses the differential diagnosis of pathological processes associated with lung cavities, focusing on infections associated with lung cavities. The goal is to provide the clinician and clinical microbiologist with an overview of the diseases most commonly associated with lung cavities, with attention to the epidemiology and clinical characteristics of the host.

Fungal Infections

The incidence of invasive fungal infections has increased dramatically over the past two decades, mostly due to an increase in the number of immunocompromised patients.1–4 Patients who undergo chemotherapy for a variety of diseases, patients with organ transplants, and patients with the acquired immune deficiency syndrome have contributed most to the increase in fungal infections.5 The actual incidence of invasive fungal infections in transplant patients ranges from 15% to 25% in bone marrow transplant recipients to 5% to 42% in solid organ transplant recipients.6,7 The most frequently encountered are Aspergillus species, followed by Cryptococcus and Candida species. Fungal infections are also associated with a higher mortality than either bacterial or viral infections in these patient populations. This is because of the limited number of available therapies, dose-limiting toxicities of the antifungal drugs, fewer symptoms due to lack of inflammatory response, and the lack of sensitive tests to aid in the diagnosis of invasive fungal infections.1 A study of patients with fungal infections admitted to a university-affiliated hospital indicated that community-acquired infections are becoming a serious problem; 67% of the 140 patients had community-acquired fungal pneumonia.8

Imaging of Bacterial Pulmonary Infection in the Immunocompetent Patient

Pulmonary infection is a common reason for imaging of the lung and a common incidental finding in immunocompetent patients. Findings on chest radiography are nonspecific in defining acute infection; however, the radiologist should be aware of classically described patterns of infection, including air space, bronchopneumonia, and interstitial patterns. The radiologist must also be aware of potential limitations of the sensitivity of chest radiography. Imaging findings at computed tomography in acute infection have been poorly studied but may be more specific. Aspiration and septic emboli are additional potential radiographic patterns of infection that may be very characteristic in appearance. In the setting of nonresolving pneumonia, the differential diagnosis includes noninfectious causes as well as a variety of atypical infectious agents, specifically, mycobacterial and fungal agents, which have overlapping but distinctive clinical and radiographic presentations.

State-of-the-Art Treatment of Coccidioidomycosis Skeletal Infections

Coccidioidomycosis is a fungal infection endemic to the southwestern United States. Typically a respiratory illness, coccidioidomycosis can rarely present as extrapulmonary infection. Skeletal coccidioidomycosis occurs in 20% to 50% of disseminated infections. Skeletal coccidioidomycosis is a chronic and progressive infection that eventually results in bone destruction and loss of function and often involves adjacent structures, such as joints, muscles, and tendons and other soft tissues. Sinus tract formation may occur. This infection may be multifocal. Although radiographs, white blood cell count scans, and other imaging methods identify and define relevant abnormalities, histopathologic examination with culture of the involved bone is the only means to confirm the diagnosis. Serologic testing is adjunctive, and complement fixation titers can be evaluated serially to assess response to treatment. A number of studies addressing the efficacy of various antifungal agents have been performed, and the results of these studies as they pertain to skeletal coccidioidomycosis are summarized herein. Among the various studies, response rates ranged from 23% to 100%, but relapse was common. A combination of medical therapy-often, itraconazole or fluconazole-and surgical débridement is often needed to control skeletal coccidioidomycosis. Early diagnosis and treatment are critical to avoid long-term problems with chronically infected bones and joints. Anatomical issues, diagnostic studies, and data related to treatment of this form of extrapulmonary coccidioidomycosis are reviewed in this article.

Coccidioidomycosis: a review and update

Coccidioidomycosis occurs in arid and semi-arid regions of the New World from the western United States to Argentina. Highly endemic areas are present in the southwest United States. Coccidioides species live in the soil and produce pulmonary infection via airborne arthroconidia. The skin may be involved by dissemination of the infection, or by reactive eruptions, such as a generalized exanthem or erythema nodosum. Interstitial granulomatous dermatitis and Sweet's syndrome have recently been recognized as additional reactive signs of the infection. Coccidioidomycosis is a "great imitator" with protean manifestations. Cutaneous findings may be helpful clues in the diagnosis of this increasingly important disease.

Central Nervous System Coccidioides immitis Infections

Coccidioidal meningitis occurs in healthy individuals and patients with AIDS or other immunosuppressive illnesses. The central nervous system infection results when Coccidioides immitis disseminates from a primary lung infection via a fungemia to reach the meninges. Cases develop primarily in individuals living in or traveling to the Lower Sonoran Life Zone of Southwest United States. Most cases begin as subacute granulomatous meningitis with occasional patients developing brain abscesses. Diagnosis may be challenging because C. immitis is isolated from cerebrospinal fluid in less than 50% of patients. However, a cerebrospinal fluid complement fixation test for IgG antibody to C. immitis has high sensitivity and specificity. Currently, optimal treatment is unclear. Standard therapy has been with life-long oral fluconazole or intrathecal amphotericin B followed by prolonged oral fluconazole. Liposomal amphotericin B given intravenously seems promising as an initial treatment as it has much higher brain penetration, less nephrotoxicity, and less severe infusion-related adverse effects than conventional amphotericin B. However, current comparative studies for efficacy of liposomal amphotericin B in coccidioidal meningitis are lacking.

Imaging of Intraarticular Masses

Intraarticular masses can be classified as noninfectious synovial proliferative processes (lipoma arborescens, synovial osteochondromatosis, pigmented villonodular synovitis, rheumatoid arthritis), infectious granulomatous diseases (tuberculous arthritis, coccidioidomycosis arthritis), deposition diseases (gout, amyloid arthropathy), vascular malformations (synovial hemangioma, arteriovenous malformations), malignancies (synovial chondrosarcoma, synovial sarcoma, synovial metastases), and miscellaneous (cyclops lesion). Knowledge of articular anatomy aids the radiologist in localizing masses to the joint space. Some joints have complex anatomy with contiguous or adjacent bursae, recesses, and tendinous connections from which masses may originate or into which masses may extend. Many of the diseases causing intraarticular masses have specific imaging characteristics, especially on magnetic resonance images, and knowledge of these characteristics will allow for a more confident diagnosis.

Clinical presentation, radiological findings, and treatment results of coccidioidomycosis involving the spine: report on 23 cases

OBJECT

This study was conducted to review the presentation and management of patients with coccidioidomycosis involving the spine.

METHODS

The authors reviewed 23 cases of spinal coccidioidomycosis treated at their institutions. There were 20 males and three females who ranged in age from 9 to 62 years. Non-Caucasian individuals were disproportionately represented. Spinal disease was the first manifestation of disseminated coccidioidomycosis in 10 cases. Thirteen patients with meningitis, soft-tissue involvement, or pulmonary involvement developed new spinal lesions despite undergoing continued systemic therapy with amphotericin and/or fluconazole. In all patients computerized tomography and magnetic resonance imaging studies demonstrated preferential involvement of the disc spaces, vertebral bodies, and pedicles with extensive paravertebral phlegmons and retropharyngeal, mediastinal, or psoas abscesses. Despite the significant imaging findings, only four patients presented with a significant neurological deficit. Local pain or radiculopathy was the most common complaint. Twenty patients underwent invasive therapy. In five patients with prominent psoas abscesses and disc space disease, drainage was performed after inserting a percutaneous catheter. Progressive bone destruction necessitated debridement and fusion in one of these patients, and two others had poor outcomes after receiving antifungal therapy alone. Initially 15 patients underwent debridement and fusion in which instrumentation (10 cases) or bone graft alone was used (five cases). One patient worsened neurologically after surgery, and another patient required reoperation for a failed fusion and to correct progressive kyphosis. Four of the 23 patients died of complications related to fungemia. Most of the 15 surviving patients have required long-term antifungal therapy for spinal and extraspinal foci.

CONCLUSIONS

Spinal coccidioidomycosis can be an aggressive disease process. Systemic antifungal therapy fails to prevent de novo spinal involvement and is usually insufficient treatment for established spinal disease.

Osteomyelitis of the clavicle: clinical, radiologic, and bacteriologic findings in ten patients

Most lesions of the clavicle are traumatic and pose few diagnostic difficulties. Nontraumatic clavicular lesions, on the other hand, are rare and frequently present problems in diagnosis. This report reviews the clinical, radiologic, and bacteriologic findings in ten patients, six of whom were diagnosed as having acute osteomyelitis and four chronic osteomyelitis. The differential diagnosis of clavicular osteomyelitis is also discussed. The clinical duration of the infectious process in these patients ranged from 2 weeks to 1.5 years. All patients presented with pain; six had fever, three had localized swelling or a mass, and three had soft tissue abscesses. The radiographic findings also varied: the lesion was predominantly sclerotic in four patients, lytic in three, and mixed in two patients; in the one patient in whom magnetic resonance imaging was the only imaging study performed, these features could not be properly evaluated. Periosteal reaction was detected in three patients. Staphylococcus aureus was the causal organism in four patients, while in the remaining six patients different microorganisms were cultured, including Coccidiodes immitis and Mycobacterium tuberculosis. Six patients required biopsy for final diagnosis. Although clavicular osteomyelitis is rare, particularly in adults, it should be considered in the differential diagnosis of a clavicular lesion. The final diagnosis often depends on the results of biopsy and cultures.

Coccidioidomycosis

Coccidioidomycosis is a largely self-limited fungal respiratory illness. However, the infrequent case of progressive or disseminated disease can be devastating. As international travel to and from endemic areas increases, physicians unfamiliar with the disease may be called upon to recognize and treat serious coccidioidal infections. The major risk factors for dissemination are race and immunosuppression. The most common sites of dissemination are the skin, lymph nodes, bone and meninges. Diagnosis is aided by investigation of the patient's clinical history, delayed-type hypersensitivity skin test reaction, serologic testing, and recovery of organisms from infected tissue or secretions for direct examination and culture. Fungicidal agents are not available, fortunately, fungistatic therapy allows many patients to recover. The availability of both intravenous/intrathecal and oral agents now allows more therapeutic flexibility in the treatment of this disease.

Ga-67 scintigraphy in chromomycosis

We examined an interesting case of chromomycosis that had a characteristic Ga-67 accumulation. This patient had had widespread chromomycosis skin lesions for 8 years. We performed Ga-67 scintigraphy in an attempt to obtain additional information on the site and extent of the lesion. Ga-67 scintigraphy revealed not only all subcutaneous nodules but also an unsuspected enlarged lymphnode and a visceral lesion. This case indicates that Ga-67 scintigraphy is a very useful method to use in detecting the site and extension of chromomycosis, especially in the nodal and the visceral lesions, and sometimes might help in differential diagnosis.