Diabetic ketoacidosis associated with pulmonary coccidioidomycosis

Susceptibility for Some Infectious Diseases in Patients With Diabetes: The Key Role of Glycemia

Uncontrolled diabetes results in several metabolic alterations including hyperglycemia. Indeed, several preclinical and clinical studies have suggested that this condition may induce susceptibility and the development of more aggressive infectious diseases, especially those caused by some bacteria (including Chlamydophila pneumoniae, Haemophilus influenzae, and Streptococcus pneumoniae, among others) and viruses [such as coronavirus 2 (CoV2), Influenza A virus, Hepatitis B, etc.]. Although the precise mechanisms that link glycemia to the exacerbated infections remain elusive, hyperglycemia is known to induce a wide array of changes in the immune system activity, including alterations in: (i) the microenvironment of immune cells (e.g., pH, blood viscosity and other biochemical parameters); (ii) the supply of energy to infectious bacteria; (iii) the inflammatory response; and (iv) oxidative stress as a result of bacterial proliferative metabolism. Consistent with this evidence, some bacterial infections are typical (and/or have a worse prognosis) in patients with hypercaloric diets and a stressful lifestyle (conditions that promote hyperglycemic episodes). On this basis, the present review is particularly focused on: (i) the role of diabetes in the development of some bacterial and viral infections by analyzing preclinical and clinical findings; (ii) discussing the possible mechanisms by which hyperglycemia may increase the susceptibility for developing infections; and (iii) further understanding the impact of hyperglycemia on the immune system.

Mycelial forms of Coccidioides spp. in the parasitic phase associated to pulmonary coccidioidomycosis with type 2 diabetes mellitus

Pulmonary coccidioidomycosis shares characteristics with other pulmonary pathologies. In tissue, spherules containing endospores are markers of Coccidioides immitis and C. posadasii infection. Mycelial forms presenting without classical parasitic structures are often misdiagnosed. The study was performed at the National Institute of Respiratory Diseases (INER) of Mexico between September 1991 and June 2005 and analyzed the association between cases, controls, and risk factors, including co-morbidity. A case was defined as any patient who presented mycelial forms and a control as any patient who presented only spherules or no parasitic forms. All patients (n = 44) with pulmonary coccidioidomycosis were diagnosed by culture, histopathology, cytology, and immunology. Type 2 diabetic patients with pulmonary coccidioidomycosis were four times more likely than non-diabetics to develop parasitic mycelial forms (95% confidence interval [CI], 0.85-20.10; P < 0.01). We formulated a comprehensive definition based on the results as follows: patients with pulmonary coccidioidomycosis with an evolution longer than 8 months, cough, hemoptysis, radiological evidence of a cavitary lesion, and type 2 diabetes mellitus, develop parasitic mycelial forms of Coccidioides spp. Based on microscopic images of patient specimens, we propose incorporating mycelial forms into the parasitic phase of Coccidioides spp. in patients with type 2 diabetes mellitus and chronic and cavitary pulmonary coccidioidomycosis.

Coccidioidomycosis in patients with diabetes mellitus

PURPOSE

The study reviewed the interrelationships of diabetes mellitus and coccidioidomycosis.

SUBJECTS AND METHODS

We conducted a retrospective review of the medical records of immunocompetent patients with coccidioidomycosis who were treated at our academic medical institution between January 1, 1999, and October 31, 2003, to compare those with and without diabetes mellitus and to determine whether glycemia correlates with the course of illness.

RESULTS

Of 329 immunocompetent patients with coccidioidomycosis, 44 had diabetes (4 type 1 and 40 type 2) and were divided into 2 groups: those with serum glucose concentrations of less than 12.2 mmol/L (220 mg/dL) and those with glucose concentrations of greater than or equal to 12.2 mmol/L (220 mg/dL). Persons with diabetes in either glucose group were more likely than those without diabetes to have cavitary lung disease (relative risk, 2.94; P<.001) and relapsed infection. However, only the diabetes group with serum glucose concentrations greater than or equal to 12.2 mmol/L (220 mg/dL) were more likely to have disseminated infection (relative risk, 2.8; P=.05) and to require treatment (relative risk, 9.85; P=.005), but their infection was less likely to resolve (relative risk, 0.24; P=.002).

CONCLUSION

Because glycemia strongly correlated with clinical characteristics of coccidioidomycosis in this cohort, we recommend routine measurement of serum glucose in persons with coccidioidomycosis to identify patients with an increased risk of complicated infection. Future studies should evaluate the efficacy of tight glycemic control on the outcome of coccidioidal infection.

The unique complications of coccidioidomycosis of the spine: a detailed time line of disease progression and suppression

STUDY DESIGN

A case report is presented.

OBJECTIVE

We report a detailed time-line of disease progression and suppression in a patient with disseminated Coccidioidomycosis of the spine. The importance of consistent and thorough treatment to prevent disease recurrence is underscored.

SUMMARY OF BACKGROUND DATA

Coccidioides immitis is a dimorphic fungus that lives as a saprophyte in arid, alkaline soils and as a parasite in the tissues of its host. Endemic to the arid soil of the American Southwest and Central and South America, its disease prevalence is increasing. There are 100,000 new infections diagnosed each year, of which 34% are symptomatic. Of the symptomatic individuals 5-10% will develop a serious pulmonary infection and of those that have a serious infection less than 1% will develop chronic pulmonary disease and/or extrapulmonary dissemination.

METHODS

A 36-year-old black woman with a 3-year history of recent migration to the desert Southwest and a family history of sarcoidosis presented to her primary care physician with shortness of breath and a cough of 2 months' duration. An anterior-posterior radiograph revealed bilateral hilar lymphadenopathy and sarcoidosis was diagnosed. The patient was placed on oral prednisone and progressively worsened. She was referred to the Orthopedic Clinic with a complaint of severe back pain.

RESULTS

Plain radiographs of the lumbar spine revealed lytic erosion of the sacral promontory. Computed tomography confirmed the sacral lesion in addition to revealing involvement of the fifth lumbar vertebral body. Over the ensuing years the patient underwent a course of operative and chemotherapeutic therapies. She endured numerous complications of the disease, one of which is being reported for the first time. Control of her disease has been accomplished through radical surgical debridement, spinal stabilization with concomitant local and systemic chemotherapy.

CONCLUSIONS

The prevalence and distribution of Coccidioidomycosis is increasing as is the likelihood of seeing its often unique and bizarre clinical manifestations and complications. If included in the differential diagnosis, the disease can be recognized earlier and the likelihood of numerous complications can be avoided. Once bony involvement is diagnosed a regimen of aggressive surgical debridement as well as consistent chemotherapy must be employed if remission and/or eradication of the illness are sought.

Aspects of fungal pathogenesis in humans

Fungal diseases have become increasingly important in the past few years. Because few fungi are professional pathogens, fungal pathogenic mechanisms tend to be highly complex, arising in large part from adaptations of preexisting characteristics of the organisms' nonparasitic lifestyles. In the past few years, genetic approaches have elucidated many fungal virulence factors, and increasing knowledge of host reactions has also clarified much about fungal diseases. The literature on fungal pathogenesis has grown correspondingly; this review, therefore, will not attempt to provide comprehensive coverage of fungal disease but focuses on properties of the infecting fungus and interactions with the host. These topics have been chosen to make the review most useful to two kinds of readers: fungal geneticists and molecular biologists who are interested in learning about the biological problems posed by infectious diseases, and physicians who want to know the kinds of basic approaches available to study fungal virulence.