Isolation of Stomatococcus mucilaginosus from drug user with endocarditis.

Stomatococcus mucilaginosus was isolated from the blood of a patient with endocarditis and a past history of drug abuse and aortic valve replacement. At autopsy, Gram stain of the aortic valve revealed gram-positive cocci. Our isolate was atypical for S. mucilaginosus in that colonies were nonmucoid and nonadherent to agar surfaces. Cellular capsules were demonstrated by light and electron microscopy. Phenotypic characteristics identified by conventional methods as well as profile numbers obtained by using two commercial identification systems for staphylococci, the API Staph-Ident and the dms Staph Trac, are presented. Practical tests that differentiate S. mucilaginosus from the genera Micrococcus and Staphylococcus include growth on nutrient agar containing salt and lysostaphin susceptibility. Additional tests that helped differentiate our isolate from group D streptococci included hydrolysis of L-pyrrolidonyl-beta-naphthylamide and streptococcal serogrouping.

Nodular colloid degeneration: distinctive histochemical and ultrastructural features.

We recently evaluated a patient with a unique form of nodular colloid degeneration. Lesions consisted of pruritic, purpuric plaques involving the upper and lower extremities and the neck. Examination of a biopsy specimen revealed large, fissured masses of amorphous material in addition to solar elastosis. The amorphous material showed negative reactions to stains for amyloid, and other histochemical studies showed results similar to those for colloid milium. The amorphous masses demonstrated a marked positive reaction to the Verhoeff-van Gieson stain for elastin. Electron microscopic examination revealed masses of degenerated elastic tissue bordered by fibrillar material that resembled amyloid morphologically. We believe this case represents a nodular form of solar degeneration with clinical and histologic resemblances to both colloid milium and cutaneous amyloidosis.

Localization of distinct surface antigens on Chlamydia trachomatis HAR-13 by immune electron microscopy with monoclonal antibodies.

Monoclonal antibodies were produced against the HAR-13 strain (A) of Chlamydia trachomatis. By an indirect immunofluorescence technique, three clones (1-7, 2-8, 9F) were found to produce antibody that reacted only with serotype A strains. Clone 3-5 produced antibody that cross-reacted with serotypes A, C, H, I, and J. Using an indirect immunoferritin technique, we examined the binding of these antibodies to strain HAR-13 by electron microscopy. Antibodies from all four clones were shown to bind to the outer membrane surface of both reticulate and elementary bodies. Two distinct binding patterns were demonstrated. Antibodies from clones 1-7 and 9F bound to the outer membrane surface in a homogeneous pattern, whereas antibodies 2-8 and 3-5 bound to the outer membrane surface in an irregular, patchy distribution. There was a direct correlation between the distribution of antigen on the outer membrane surface and neutralization of C. trachomatis HAR-13 infectivity in vitro. Neutralization of HAR-13 infectivity by antibodies 1-7 and 9F was complement dependent, whereas antibodies 2-8 and 3-5 did not neutralize under any conditions.

Ultrastructural analysis of the effects of erythromycin on the morphology and developmental cycle of Chlamydia trachomatis HAR-13.

The effect of erythromycin (10 micrograms/ml) on the morphology and developmental cycle of Chlamydia trachomatis HAR-13 was examined by electron microscopy. When the antibiotic was added later than 24 h post infection, the HAR-13 morphology or developmental cycle was not altered. Addition at 18 or 24 h post infection inhibited glycogen production, blocked the transformation of the reticulate body to elementary body, and produced ghost bodies and reticulate bodies twice the diameter of untreated reticulate bodies. When erythromycin was added within 12 h post infection, the conversion of the elementary body to reticulate body was inhibited. Erythromycin (10 micrograms/ml) was bactericidal to strain HAR-13 throughout the developmental cycle.

Ultrastructural effect of penicillin and cycloheximide on Chlamydia trachomatis strain HAR-13.

The effect of cycloheximide and penicillin on the ultrastructural morphology of C. trachomatis strain HAR-13 was examined by electron microscopy. HAR-13 infected McCoy cells were either treated with cycloheximide (1 microgram/ml) or cycloheximide (1 microgram/ml) plus penicillin G (100 U/ml). The studies revealed that cycloheximide alone induced no morphological alterations into the ultrastructure of HAR-13. Both HAR-13 developmental forms, the elementary body and reticulate body, were present inside the treated McCoy cells. The elementary bodies contained the central dense nucleoid and were about 0.3 microns in diameter, while the reticulate bodies were of typical gram negative bacterial morphology and were from 0.5-1.0 microns in diameter. Cycloheximide in combined treatment with pencillin produced giant, swollen reticulate bodies that were 2-4 microns in diameter and in some cases vacuolated. Elementary bodies were noticeably absent. These results indicate that cycloheximide does not alter the morphology of HAR-13. This system is a useful model for studying the ultrastructural morphology of C. trachomatis strain HAR-13.

Fabry's disease. Primary diagnosis by electron microscopy.

Fabry's disease is a lipid storage disease found in children and adults. The lipid is stored as a myelin-figure-like whorl of membranes in endothelial and smooth muscle cells, myocardium, fibroblasts, and epithelial cells of the glomerulus. The lipid deposits are identifiable by light microscopy, but are much easier to demonstrate by electron microscopy. The disease leads to vascular insufficiency because of narrowing and thrombosis of arteries and arterioles. The resultant vascular insufficiency leads to peripheral neuritis, myocardial infarction, peripheral infarction and cerebral infarction. Corneal clouding due to lipid deposits is also seen. Renal involvement is widespread, but renal failure occurs late.

Electron microscopy of lymphatics of the porta hepatitis.

The ultrastructure of the lymphatics of the porta hepatitis at the junction with the liver parenchyma has been examined. The lymphatics are composed of endothelium composed of flattened cells containing occasional mitochondria, pinocytotic vesicles and nuclei. The cells are bound by maculae adherentes, zonulae occludentes and desmosome-like structures. There are occasional fibers between endothelium and underlying collagen. Occasional pores closed by diaphragms are present. There is very little basement membrane. There is no definite communication with the spaces of Mall and Disse, but the lymphatic lumens are separated from these areas only by the junctional processes, which may be permeable. Lymphatics are present only in collagenized portal areas and not in the liver parenchyma proper.

Immune complex disease associated with an infected ventriculojugular shunt: a curable form of glomerulonephritis.

A 22-year-old man with a ventriculojugular shunt had edema, hematuria, proteinuria, hypocomplementemia, azotemia, and S epidermidis bacteremia. Initial percutaneous renal biopsy showed a diffuse proliferative glomerulonephritis. Subendothelial and intramembranous deposits were seen on electron microscopy. Immunofluorescent studies were positive for IgG and C3. A repeat percutaneous renal biopsy six weeks after cessation of antibiotic therapy revealed a mild proliferative glomerulonephritis with some evidence of resolution. No deposits were seen on electron microscopy and immunofluorescent studies were negative. At elective shunt revision three months after cessation of therapy, culture of the jugular portion of the removed shunt revealed S epidermidis. Early recognition of immune complex glomerulonephritis occurring with an infected ventriculovascular shunt should permit early treatment (antibiotic therapy and removal of the infected foreign body) and a favorable outcome.

Neutralized lanthanum solution: a largely noncolloidal ultrastructural tracer.

Lanthanum nitrate solution adjusted to pH 7.4 and pH 7.7 was subjected to column chromatography, ultrafiltration and conductivity measurements. Lanthanum concentration was measured by a colorimetric method employing eriochrome cyanine RC. Under these conditions, lanthanum was not excluded from the column by a packing with an exclusion limit of 1800 daltons. Ultrafiltration through a membrane with a filter limit of 500 daltons allowed approximately 75% of the lanthanum to pass. Conductivity measurements showed a decrease of charge of about 20% on adding sodium hydroxide to a solution of lanthanum nitrate up to a pH of 7.7. It is concluded that approximately 80% of the lanthanum exists as a charged particle of less than 500 daltons at pH 7.7; the other 20% consists of larger, possibly colloidal particles. Nonfiltered and ultrafiltered lanthanum have equally good staining and tracer properties in the electron microscope, suggesting that staining depends largely on the ultrafiltrable noncolloidal lanthanum ion.