A urinary marker for occult systemic coccal disease.

Gram-negative particles, found in 'normal' urine by an improved microscopic technique, become excessive (often > 10(5)/ml) in many systemic diseases. In these diseases they are accompanied by sparse, usually fastidious, gram-positive cocci. Antibiotics at moderate doses usually have little effect. Larger doses of antibiotics suppress, or temporarily eliminate, the particles. In this report, the particles are characterized by light microscopy for better identification. Then, by detection of muramic acid in a hydrolysate and by transmission electron microscopy, they are identified as decomposed ('exploded') gram-positive cocci. Since explodeds cannot be external contaminants, and their precursors cannot proliferate sufficiently in urine, they must have crossed renal membranes to come from within the body. They are demonstrated in tissue fluids and in synovial fluids by optical microscopy, by their muramic acid, and by transmission electron microscopy. Thus, they cross other membranes. Explodeds are excessive in several rheumatic diseases, in renal diseases, in diseases in which a coccal cause has been sought, and in some in which cocci have never been considered. There is no precedent for explodeds. Their appearance and numbers are compatible with the literature on natural and experimental systemic streptococcal diseases and with the experimental illnesses following injection of streptococcal cell walls. Urinary explodeds are likely to be the end result of the 'almost physiological' entry of streptococci into the circulation which necessitates predental antibiotic prophylaxis in mitral disease. Increased numbers of urinary explodeds probably represent excessive entry of precursors or proliferation of precursors within the host. Urinary explodeds serve as a marker for diverse systemic diseases, systemic coccal disease.

Computer algorithm offers a comprehensive view of quantitative bacteriuria.

Using improved microscopy of urine sediment, the consistent finding of bacteria, usually gram-positive cocci at low counts, free or even in casts, in the sediment of carefully collected urines from patients with systemic illnesses has led to the need to reconsider their exclusion by the customary criteria for 'significance' of bacteria in urine. Since 'significance' is currently based upon mathematical assumptions limited to high counts (> 10(5) colony-forming units/ml) for the prediction of clinical pyelonephritis alone, a digital computer program was created to predict the full spectrum of the expected concentration of bacteria in bladder urine versus time for a very wide range of possible bacterial division times, bladder kinetics and urine flow rates. Curves generated resulted in the discovery of very simple rules based on an easily calculated discriminant, the host's critical division time (CDT) for any bacterial species in his urine. (1) If the division time in the urine of a species entering the urinary tract is shorter than the CDT, the bacteria will proliferate to > 10(5) cfu/ml. Published data on growth in human urine show that very few bacterial species can divide so fast in urine, and those are the ones currently considered 'significant'. Except for some enterococci, streptococci cannot. (2) With a division time only marginally longer than the CDT, any bacterium would wash out unless continuously supplemented via the kidney or from the bladder wall. (3) With a continued supplement and the longer division time, the concentration would fall to a low plateau, and that plateau is diagnostic of a continued supplement. The cocci observed by microscopy are fastidious or dead. They grow poorly if at all in urine, and thus are not likely to ascend the urinary tract. Their appearance corresponds to the earlier studies of bacteriuria and to the known excretion of blood-borne bacteria in natural disease, whether or not there are anatomical changes in the kidney. It is suggested that the low-level coccal bacteriuria found is a marker for scent bacteremia in many systemic diseases for which a bacterial provocation has been sought.

Improved microscopic detection of bacteriuria.

A simple method is described which permits the microscopic detection of bacteria in sediments of urine and other fluids, including bacteria that have eluded detection by conventional means. The method introduces increased centrifugal force and stepwise chemical fixation and then conventional staining. It is rapid, economical, and suitable for use in a physician's office. Use of this method immediately reveals those bacteria reported as "significant" by the conventional laboratory culture. More importantly, living or dead, which are missed by the conventional culture and by the conventional Gram staining procedure. These bacteria usually can be grown in special media and they appear to be related to systemic disease as evidenced by the clinical response to appropriate antibiotics.

Acquired iron-deficiency anemia caused by an antibody against the transferrin receptor.

We report a case of anemia due to autoantibodies to the transferrin receptor interfering with iron incorporation by erythroid progenitors. A previously healthy woman with severe acquired microcytic anemia had increased serum iron levels, electrophoretically normal transferrin concentrations, and very high levels of free protoporphyrin in red cells. The bone marrow had no stainable iron but had an excess of normal-appearing plasma cells. Erythroid precursors stained with fluorescent mouse antihuman IgM. The serum contained an antibody that reduced 59Fe incorporation by erythroleukemia K562 cells in vitro but did not inhibit iron transferrin binding. An IgM fraction of the patient's serum immunoprecipitated the human transferrin receptor obtained from solubilized [35S]methionine-labeled K562 membranes. Binding of [59Fe]transferrin or fluorescent iron transferrin was not diminished by the patient's serum at 4 degrees C, but at 37 degrees C uptake was markedly reduced, as was the binding of fluorescent monoclonal antibodies to either surface transferrin or the human transferrin receptor. A complete clinical and hematologic remission occurred with azathioprine and prednisone therapy. We conclude that the patient's autoreactive IgM down-regulated the number of transferrin receptors and diminished iron incorporation by erythroblasts, leading to an iron-deficiency anemia.

Acquired iron-deficiency anaemia due to impaired iron transport.

A previously healthy 39-year-old woman presented with severe iron-deficiency anaemia, but she had lost no blood and her serum iron level was high. Her bone marrow was hypercellular with a predominance of erythroid elements and had no stainable iron deposits, but it also showed dyserythropoiesis and an excess of apparently normal plasma cells. IgM was demonstrated on her bone-marrow erythrocytes and their precursors. On azathioprine and prednisone therapy she had a complete clinical and haematological remission. The impaired iron transport and the associated dyserythropoiesis were probably due to an IgM-mediated autoimmune process. Diabetes mellitus, which first appeared during her anaemic illness, could also have been due to an autoimmune process. This is the first report of an iron-deficiency anaemia caused by a naturally acquired impairment of iron transport.

Electrogenesis from an ATPase-ATP-sodium pseudo pump.

The short circuit current and the open circuit voltage responses of membranes to ATP, which have been attributed to membrane ATPase acting as a sodium pump, have been reproduced not only in a lipid membrane containing solubilized ATPase but also in membranes formed of the phospholipids contained in ATPase. The response is greatest with cardiolipin, but occurs with other acidic phospholipids. This observation of electrogenesis without hydrolysis is a surface phenomenon probably due to the alignment of ATP on the phospholipid by ion association at its interface with the water phase. The finding constitutes a precaution for interpreting studies of membrane Na-K-ATPase or for its incorporation into an artificial membrane. The substances necessary for electrogenesis are present at the mitochondrial membrane, and the particular orientation of the ATP on the phospholipids in vitro suggests a role for this ion association in the function of Na-K-ATPase.

Some observations on the partition of Na+ and K+ into a lipid phase.

It is likely that sodium and potassium must traverse a lipid membrane surrounding cells and that this membrane has to do with intracellular cation selection. Electrolyte theory is inadequate to predict the partition of salts of these cations between water and a lipid phase. The data obtained here demonstrate the partition and the cation selection to be a function of the anion species (or ionized lipid), the solvent and the presence of the unionized form of the lipid. Specificity in lipid partition is not synonymous with the cation specificity in precipitation of ionic crystals.