Peptidoglycan types of bacterial cell walls and their taxonomic implications.

Management of pilonidal sinus is frequently unsatisfactory No method satisfies all requirements for the ideal treatment--quick healing, no hospital admission, minimal patient inconvenience, and low recurrence--but greater awareness of the strengths and weaknesses of existing methods would lead to improved management Early excision of the pilonidal pit at the time of treatment of pilonidal abscess reduces the high (40 per cent) risk of subsequent sinus Treatments for pilonidal sinus that flatten the natal cleft halve the risk of recurrence En block excision of pilonidal sinus with secondary healing should be abandoned and emphasis given to development of treatments, such as primary asymmetric closure, which have more potential Some treatments are operator-dependent and, to achieve the best results, junior surgeons must be correctly trained and supervised Future treatment studies must be prospective and randomized, and should compare healing time, recurrence rates beyond 3 years, nurse and hospital visits, patient inconvenience and loss of income

Pilonidal sinus: finding the right track for treatment.

Eighty strains of anaerobic coryneforms were compared with 29 strains of classical propionibacteria and 8 strains of Arachnia propionica by cell wall analysis, deoxyribonucleic acid (DNA) base compositions, and nucleotide sequence similarities. The anaerobic coryneforms have DNA base compositions in the range of 58 to 64% guanine + cytosine (GC) and show at least three homology groups. The largest group corresponds to organisms identified as Propionibacterium acnes and shows about 50% homology to strains in the P. avidum homology group. The third group, P. granulosum, shows low levels of similarities to the other two. All strains of anaerobic coryneforms have some combination of galactose, glucose, or mannose as cell wall sugars, and most have alanine (ala), glutamic acid (glu), glycine (gly), and l-alpha-epsilon-diaminopimelic acid (l-DAP) as amino acids of peptidoglycan. However, a few strains in the P. acnes and P. avidum homology groups have meso-DAP and minimal amounts of glycine. Two serological types, based on cell wall antigens, were found in the P. acnes homology group. One type had galactose, glucose, and mannose as cell wall sugars, the other glucose and mannose only. The classical propionibacteria have DNA base compositions in the range of 65 to 68% GC and show four homology groups which correspond closely to van Niel's classification as given in the 7th edition of Bergey's Manual. The P. jensenii group showed about 50% homology to the P. thoenii group and about 30 to 35% to the P. acidi-propionici group. The P. freudenreichii strains showed a rather lower level of similarity (8 to 25%) to the other homology groups. Most of the strains of classical propionibacteria also have some combination of galactose, glucose, or mannose as cell wall sugars and ala, glu, gly, and l-DAP as peptidoglycan amino acids, but P. shermanii and P. freudenreichii strains, which form a single homology group, have galactose, mannose, and rhamnose as cell wall sugars and ala, glu, and meso-DAP in their peptidoglycan. There is a rather low level of DNA homology (10 to 20%) between the anaerobic coryneforms and classical propionibacteria. However, the strains of A. propionica which have a GC content of 64 to 65% and form a single homology group, show no homology to either of the other two major groups.

Cell Wall Composition and Deoxyribonucleic Acid Similarities Among the Anaerobic Coryneforms, Classical Propionibacteria, and Strains of Arachnia propionica

Corynebacterium diphtheriae and Its Relatives

Bacterial flora of the normal human skin.

The organism known as the \"acne bacillus\" in medical literature was first observed by Unna (1896) in histological sections of acne comedones, but Sabouraud (1897) was the first to cultivate this organism successfully in pure culture from the contents of acne pustules. Subsequent studies on the etiology of acne vulgaris by Gilchrist (1900, 1903), Hall6 and Civatte (1907), Hartwell and Streeter (1909), Fleming (1909), Suldmerson and Thompson (1909), and Molesworth (1910) indicated that the acne bacilli were morphologically similar to the corynebacteria but differed markedly from these organisms in showing a strong preference for anaerobic conditions. Gilchrist (1900) named the organism Bacillus acnes, whereas Bergey et al. (1923) placed it in the genus Corynebacterium because of its morphological relationship to the members of this group. Our interest in these organisms became aroused following the observation of Weiser and Gunter (1942) of this laboratory that samples of human blood plasma destined for a civilian plasma bank contained anaerobic diphtheroids as one of the principal contaminants. These workers were able to show that such organisms occurred on normal skin and probably gained entry into the blood plasma as the result of ineffective skin disinfection preceding venipuncture. The anaerobic diphtheroids isolated from plasma and skin seemed to fit the general description of Corynebacterium acnes (Bergey et al., 1939), but, as the inclusion of such organisms in the genus Corynebacterium seemed questionable to us, we considered it worth while to make a comparative study of a series of isolates and the available authentic cultures of C. acnes in an attempt to clarify their taxonomic position. It also seemed desirable to obtain quantitative data on the occurrence of these organisms on normal human skin.

Shirley E. Gunter

Papers

The Taxonomic Position of Corynebacterium acnes.