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Newfield RS. Vargas I. Huma Z.: Eikenella corrodens infections. Case report in two adolescent females with IDDM. Diabetes Care. 19:1011-3, 1996OBJECTIVE: To alert physicians caring for patients with diabetes to the microorganism Eikenella corrodens and to discuss the appropriate preventive and therapeutic measures to take against this potentially morbid opportunistic Gram-negative bacilli.CASES: We present two cases of extra-oral E. corrodens infections in adolescent females with IDDM. The first patient had diabetes of 4 years' duration, which was moderately well controlled. Chronic finger biting resulted in a complex felon that evolved gradually and worsened while the patient received cephalexin orally. Delay in seeking further intervention resulted in necrosis of her distal fingertip and nail bed. The second patient had poorly controlled diabetes for 5 years. She developed an acute thigh abscess at an insulin injection site that resolved after drainage and intravenous antibiotics.CONCLUSIONS: E. corrodens commonly inhabits the human oral cavity and becomes a pathogen mostly when host defenses are impaired, causing abscesses and infections that are at times fatal. Patients with IDDM are compromised hosts and with daily microtrauma to their skin via glucose monitoring and insulin injections, are prone to develop E. corrodens infections that can be introduced through oral secretions by licking or biting their skin. Educational efforts aimed at preventing exposure of traumatized skin to oral secretions can minimize the risk of E. corrodens infections in compromised hosts.Early intravenous administration of antibiotics, bearing in mind E. corrodens resistance to clindamycin, metronidazole, and other antibiotics, coupled with prompt surgical intervention, is essential in successfully managing E. corrodens infections.

Monocytes are phagocytes which remove injured and dead cells, cell fragments, microorganisms and insoluble particles from the blood and body tissues.Monocytes also secrete substances that affect the function of other cells, especially lymphocytes.They are produced in the bone marrow, and when mature are released into the peripheral blood. Although they do serve a phagocytic role in the blood, their main site of action is the body tissues.The half-life for monocytes in the peripheral blood is approximately 8 hours. Monocytes migrate into the tissues, often to sites of inflammation, where they serve their primary purpose.Here they transform into fixed or free macrophages, and continue their function as avid phagocytes.When activated, macrophages may enlarge and have enhanced metabolism.

N:C Ratio - Nuclear: cytoplasmic Ratio - The ratio of nuclear volume to cytoplasmic volume within any one cell.Neoplasm - Any new and abnormal growth, such as a tumor.Neutrophilic Granules - Specific granules present in the cytoplasm of neutrophils. These granules resemble pencil stippling and stain a lilac color due to their affinity for both basic and acid dyes.Phagocyte - Any cell that ingests microorganisms or other cells and foreign particles.Phagocytosis - The ingestion and destruction of microorganisms or other foreign particles.Plasma - The fluid portion of blood in which the various blood cells are suspended.PF3 (platelet Factor 3) - A lipoprotein component of the platelet membrane; functions as a surface catalyst during blood coagulation.Pseudopod - A temporary protrusion of the cytoplasm of a cell.Refractile - Capable of refracting or changing the direction of light.Senescence - The process or condition of growing old.Serotonin - A constituent of blood platelets and other cells and organs; induces constriction of the blood vessels.Specific Granules - Granules found in cells of the more mature stages of the granulocytic series. They have distinct staining reactions which differ with each type of granulocyte.T-cell - Thymus derived lymphocyte which mediates cellular immunity.Thrombocyte (Platelet) - A circular or oval disk found in the blood; concerned with hemostasis.Thymus - A ductless gland-like body situated in the anterior mediastinal cavity; reaches its maximum development during the early years of childhood.Vacuole - Any small space or cavity formed in the cytotoplasm of a cell.

When a neutrophil is faced with a microorganism or foreign particle, phagocytosis begins. The neutrophil extends pseudopods around the foreign material and engulfs it. Digestive enzymes present in the neutrophilic granules are released into the vacuole containing the foreign particle, and the particle is destroyed. In most cases a mild infection enhances the function of neutrophils while a severe infection impairs their function.

View control smears under oil immersion. If the control smears stained correctly, read the remainder of the smears.Look at the direct smear macroscopically to locate the stained area.Examine the direct smear under oil immersion and find an area that is properly decolorized.Examine at least ten fields in an area that is properly decolorized.Identify the following nonbacterial cell types: epithelial cells, white blood cells, red blood cells, yeast and hyphae.Look for microorganisms and record their characteristics.Quantitate each type of element found and record on the work card.Interpret the direct smear result.Report the direct smear finding.

Microorganisms that are Gram positive stain blue while those that are Gram negative stain pink.

The process of culture, isolation and identification of microorganisms is basic to medical microbiology. When a culture shows signs of growth, the process of identification includes examining the following characteristics:appearance of the colonies in the culture mediumstaining reactionappearance of stained organismssizeshapearrangement of bacterial cellsThis type of preliminary identification may help the physician to initiate the appropriate antibiotic treatment.