Complete Text (Part 13)

is more common 1<8 and cliionic in women. A decrease in the nnniber c. stools may be due to impaction of fecal masses in tlie rectum. In many cases these can reached Avith the linger and dislodged or broken up. 1.'). ^[egalo-cohni. (Hirschsprung's disease.) There is a congenital weakness of the wall of the colon. The bowels may move once a week, once a uiontli, and one case is reported of once a year. The-c patients present all the signs of constipation. 14. Ty|>hoid. This is associated frequently with con ti])ation, especially in the early stages. During ilu stages of ulceration profuse watery and foul- siiulling stools occur. They may be yellowish-green in coh)r and give rise to the term "pea soup stools." Hemorrhages are frequent which are usually pre- ceded by oozing and the appearance of occult blood. Clinically, this indicates the cessation of hydro- therapy and feeding. Typhoid cultures are easily obtained. 15. Cholera. The stools are usually profuse with an abundant watery discharge, although moderate cases show only a moderate amount of diarrhea. Flakes in mucus, rice-like in appearance, give the term "rice-water stools." 16. Amoebic dysentery. This sometimes runs an intermittent course. There are periods of intense diarrhea, followed by periods of normal stools and even constipation. Amoebae are foUnd in the patches of bloody mucus. 17. Tuberculosis. There is a great variation in the stools, which depends upcn the site of the lesion. In tabes mesenterica there is an interference with absorption, and one finds an excess of fatty acids and soaps in the stools. This is unlike pancreatic disease, where an excess of neutral fat and fatty acid occur. Dietary indiscretions lead to great diarrhea. J 159 A. OUTLIXE OF ROUTINE FOR MAKING QUAL- ITATIVE EXAMINATIONS OF BLOOD. I. Cleaning glass ware (slides and cover slips), a. Gj-oss cleaning — several methods. (1) Wash with soap and water, then with much clean, hot water (never allow the water to cool till all the soap is re- moved), followed by distilled water, finally put in 95% alcohol (may be put into ether or chloroform after alcohol). (2) Soak in acid mixture (cone, nitric acid or a mixture of sulphuric acid and po- tassium bichromate) for 6 to 24 hours, then wash thoroughly in clean water, then distilled water. Finally run through two thorough washings with 95% alcohol and put in ether or chloro- form (ether may be omitted — keep in alcohol — closed vessel) . b. Fine cleaning. (1) Keep in alcohol (ether or chloroform), and when needed polish with a clean cloth (old linen preferable) absolutely free from grease and dust. Ex. unfold an old but clean and ironed handker- chief— use the inside surface which no linger has touched. (2) Take from alcohol (ether or chloroform) and polish, keeping them in a clean, dry, well-closed receptacle until used. Ex. A closed glass dish. (Avoid Avooden or pasteboard boxes, as fragments fall from such materials.) (3) Never hold with fingers, always use clean forceps to handle glass ware. (4) Dust off with clean camel's hair brush before us^ing. 160 (5) It is oCteii advantageous to blow across glass ware just before placing blood on it — care must be exercised that no parti- cles of saliva fall on glass. 1 1, flaking smears. a. Preliminary details. (1 ) I^e glass Avare cleaned in manner sug- gested under T. Cover glasses must be square ( round will not do) ; cover glasses must not be too thick, as oil immersion cannot be focused upon preparation ; size 22 mm. preferable, thickness Xo. 1 essen- tial. (2) Glass Avare must be flat — avoid concave surfaces — blood will not spread. ( .") ) Dip blood sticker in alcohol before using (never flame sticker — dulls point). (1) Wash skin with alcohol and dry before sticking. Alcohol frees skin from grease and is antiseptic ; drying prevents blood drop from spreading over skin. (5) Avoid CA'anosed areas and aA^oid cyano- sis by squeezing area Avhich is to be stuck, in order to make the blood floAA\ Blood examinations from such areas are useless for many purposes. (()) Stick deep enough to bring from 2 to 4 drops of blood— preferably without the assistance of any pressure. While any pressure is undesirable, a slight amount is sometimes necessary. (7) Wipe off the first drop — use the second, Avhich is more representative of actual blood picture. b. Actual smearing. (1) CoA^er slip method. (a) With instruments. 161 1 . Plokl cover slip Xo. 1 in cross bill forceps. 2. Hold cover slip Xo. 2 in clean, plain forceps. .). Brush the cover slip Avith a clean camel's hair brush to remove any lint or dust. 4. Place drop on cover slip Xo. 2. Drop should be size of small black-headed ])in. Let it reach the cover slip by capillary attraction. Xevei' touch skin with cover slip. 5. With drop on cover slip Xo. 2, j)lace cover slip Xo. 2 on cover slip Xo. 1 in such a maner that tl'.e dro]) is sj)read without caus- ing bubbles. (Ex. Let cover slip X'^o. 2 come down so that cover slip Xo. 1 touches edge of drop first and gradually touches whole drop — or let the drop reach the first cover slip by capillary at- traction). 0. Let drop spread until it has almost stopped spreading — expe- rience is needed for this. 7. Pull cover slip in an absolutely horizontal numner. Any tendency to a vertical pull will ruin the preparation. (Holes in the smear will result.) 8. Place preparations (smear side up) on a clean paper and allow them to dry in the air. 9. Protect smear from insects, ants and flies especially, as they will ' quickly ruin smear. 162 (b) Without instruments. Cover slips may be bandied by the lingers instead of Avith forceps in making smears provided tbe following precautions are ob- served : 1. Use forceps to take cover slips from the clean container. 2. Hold cover slip between fingers so that only the edges are touched and never the surface of the glass. 3. Cover slip No. 1 is held in left hand, usually between thumb and forefinger. Place drop on cover slip Xo. 2, Avhich is held in right hand, and then proceed to make the smear as directed above, with the exception that the pulling is done by holding the cover slip with the fingers rather than with forceps. (2) Slide method (use of slides instead of cover slips). A drop, larger than the one used for cover slip method, is placed on a slide and drawn across it so as to make a smear. Various methods for spreading are suggested. (a) By means of a second slide, prefer- ably with a beveled edge and of a width less than the slide on which the smear is to be made (i. e., break off a corner of a slide to make it nar- rower)., (b) A small glass rod (w^idth less than slide), to which another glass rod has been fused, to serve as handle, in such a way that the combination 163 looks like a T. The cross-beam of the T is used as the spreader. (CI (Mgarette paper, hat pius, long needles, or plain glass rods may also be used as the spreading agent. (d) The spreader (whichever method suggested being used) may be placed to the left of the drop, and the blood in this way pulled across to the right, or fe) The spreader may be made to touch the drop from the right and the drop pulled across the slide to the right. (This method is to be pre- ferred.) (f ) Tlie thickness of the spread can be varied by changing the degree of angulation of the slide and spreader. (X.B. — The drop should be placed well to the left of the slide, so that a long spread may be pulled to the right). c. Criteria for good smears. (1) Smooth, even spreads, with R. B. C. lying flat (never in rouleaux)). Their edges may touch, but there must be no overlapping. (2) At least 8 such areas (low power) with- out holes and without streaks are re- quired to constitute the minimal re- quirement for a good smear. d. Relative merits of cover slip and slide methods. ( 1 ) The cover slip method gives a much bet- ter distribution of W. B. C. and is the method necessary to use in making dif- ferential W. B. C. counts. 164 (2) The slide method gives a good distribu- tion of K. B. C. The large W. B. C. (polymorphonuclear and large mono- nuclear) are pushed to the edges and the lyphocytes remain scattered through the spread. This makes satisfactory dif- ferential counting impossible. When E. B. C. are to be examined for parasites, the slide method is superior to the cover slip method, inasmucli as more fields are available for study and the E. B. C. dis- tribution is as good as Avith the cover- slip method. III. Making stained preparations, a. With Wilsoji stain. (1) The stain. A modified Eomanowski stain — a polychrome methylene blue- eosin stain. (For details of making it see Emerson, Webster, etc.) (2) Technique of applying stain. (a) Use freshly made smear for stain- ing; smears 2 to 4 days old do not stain so Avell as those stained very soon after making. (b I Place preparation with smeared sur- face up (smeared surface has not the gloss of the clean glass surface) in staining forceps on the edge of a table or on a cork for support in such a manner that it may easily be taken up Avith a pair of forceps. (c) With a dropper drop 6 to 8 drops of Wilson stain on the smear, being careful to avoid shaking the bottle of stain before using it in order to keep stain free from any precipitate which may be present. Let the stain 165 remain on the smear 60 sec. (using second hand of watch for accurate calculation) ; then (d) Add the same number of drops of distilled water, and let the prepara- tion stand an addition 4 min. (by the watch) ; then (e) Taking the cover slip with forceps (preferably staining forceps to pre- vent possibility of dropping cover glass) and holding it carefully in a perfectly horizontal manner so that the scum which has formed on the surface may not touch the glass, float off rather than wash off the scum with a stream of water (pref- erably distilled), which is at first run very slowly, and then more briskly so as to free the smear from all traces of excess stain. All this time the cover slip is held abso- lutely horizontally. Washing should take from 5 to 8 seconds. (X. B. — 1. For staining, do not hold smear with any forceps used for liulling smears — forceps used for pulling smears must be kept abso- lutel}^ clean. 2. Each fresh supply of stain re- quires a new formula for stain and water combination. In general equal numbers of drops of stain and water are used.) (f ) After washing is completed, the cover slip, still held in the staining forceps, is tilted and the lower edge touched to a blotter, so that the 166 excess of water is quickly drained off. (N. B. — If the cover slip be held with any forceps other than stain- ing forceps, great care must be ex- ercised to j)revent fluid collected at the forceps' tip from running over the preparation and streaking it. If any such forceps be used, it is best to tilt the cover slip immediately after washing, in such a manner that the excess of water on the cover slip runs toicard the forceps. Remove the cover slip from the for- ceps and holding it in the hand, drain off the excess of water by touching an edge to a blotter. (Pref- erably that edge held previously by the forceps.) (g) After washing, the smears are dried in one of the following ways : 1. By air drying : a. Generally by placing the smear against some sup- port and letting one edge rest on a blotter, b. By waving it gently in the air, holding it with either for- ceps or finger (touching only the edge of the cover slip if the finger method is employed). 2. By blotting : Place preparation between layers of fine blotting paper (it must be absolutely free from dust). Apply light pressure to the upper layers of the blotting paper to facilitate drying. Then pick up the preparation and remove it to a dry place, and again apply light 167 pressure. Be careful not to push the smear along the blotter nor to press too heavily, for holes and streaks in the preparation will be the result. (N. B. — The staining is thought to be better if the blotting method is employed, but many good smears have been ruined by slight negli- gence in the manner of blotting.) (h) After drying the preparation (if it be a cover slip), mount it in Can- ada balsam {acid free) in one of the following ways : 1. Preferably smear side down as the preparation is then protected from insects and any acid or alkali in the air. 2. Smear side up if the cover slip is too thick to permit focusing the oil immersion when mounted smear side down. (N. B. — If slides are used instead of cover slips, the technique is iden- tical except that the preparation is not mounted, and for examination oil immersion is applied directly to the surface of the smear.) (l) Criteria for a good stain. R. B. C. — Are of a buff color, neither lemon nor red. Platelets — Are well stained — nuclear purple blue stain, with the architecture plainly visible. W. B. C. — Are stained as follows : Polymorphonuclears. P. M. N. — Nucleus — Deep purple, retic- 168 ular, chromatin pronounced, more poly- morplious than |)olynuclear. Grannies — May or may not be seen ; vary in size ; pink or yiolet. rrotoplasm— Faint pink. r. M. E. — Nucleus — Larger than P. M. X., fewer lobes; takes lighter purple color ; reticulated. Granules — Large, round or oyal; bright red; tend not to oyerlie nucleus. Protoi)lasm — Faint pink. P. M. B. — Nucleus — Chromatin scanty, stains light purple. Granules — Large, yary in size; jiurple to black; generally some oyerlying nucleus. Protoplasm — Faint pink. Lymphocytes. — Nucleus — Large, round or oval ; slightly notched, chromatin pro- nounced, deep purple ; clear zone outside. Granules — Normally none; old cells (?) sho\v azure granules ; red yiolet ; yary in size ; few to a cell. Protoplasm — Scanty, crescentic ring; homogeneous sky to deei) blue; slightly reticulated. Large Mononuclears. — Nucleus — Large, oyal, indented, horse shoe, kidney or yery irregular shape ; chromatin poor ; light blue or purple color; generally ec- centric. ProtoiDlasni — Abundant, often irregular, clear, reticulated, pale blue (reticulated nodosities giye granular ap- pearance). Granules — None (azurophil- ogranules frequent). Malarial parasites are beautifully stained with Wilson stain. The areas between the cells must be clear and free from all suggestion of stain. The cells must stand out with distinctness T\ith jio suggestion of hazy edges. There must 169 . be no precipitate present. (4) Common pitfalls in staining with Wil- son stain. (a) Precipitate on the preparation. 1. Due to: a. Faulty washing, l)y not holding preparation horizontal and floating otf scum, thus permit- ting the scum, which ahvavs forms, to touch the smear, b. Permitting dust to settle on the smear. 2. Prevented bv: a. Holding the preparation horizontal all during the washing and learning to play the stream of water in washing to the best advantage, b. Keeping the smears clean during tlie interval which elapses between pulling and staining. (b) An indefinite serum-like stain be- tween the cells, due to insuflicient washing. (c) Tearing preparation by improper blotting. (d) Deterioration of stain supply due to: 1. Acids kept in the same locker. 2, Water from mixing pipettes or putting stain in bottle waslied witli water. b. With Jrinio' stain. (1 I The stain. A simple methylene blue- eosin, alcoholic staiu. (For details see Emerson, Webster, etc. i (2) Technique of a])plying stain, (a) Freshly made smears stain better than those 24 to 48 hours old. (b) Staining, washing, blotting and 170 mounting are carried out in a man- ner like tliat described under Wilson stain with the following differences : 1. Place 6 to 8 drops of stain on the smear and leave for 2 min. (use watch for timing) ^ then add the same number of drops of water and leave for an additional 2 min. (use watch), wash and dry. (N. B. — With each fresh supply of stain a new formula for the stain and water combination, as well as for the time relation, is necessary). (3) Criteria for a good stain. E. B. C. — Are of a darker color than the K. B. C. with Wilson stain, pink rather than buff, although it is possible and advisable to have them look as much like the R. B. C. of the Wilson stain as possible. Platelets — Stain rather jDOorly — a pale blue. W. B. C. are stained as follows : The nuclei are not so well stained as with Wilson stain, but granules stand out well. Polymorphonuclear — Nuclei blue, but distinctly paler than with the Wilson stain. Neutrophile granules a deep pink. Eosinophile granules a very deep pink. Basophile gran- ules purple blue. Lymphocytes — Nuclei a moderate- ly pale blue, protoplasm tinged with blue. Mononuclears — Nuclei paler blue than those of the lymphocytes, proto- plasm a faint blue Azurophilic 171 granules