Herbert Begemann

Lymph Nodes and Spleen

Lymph node puncture is a simple procedure that has become an indispensable part of hematologic diagnosis. It can be performed anywhere and at any time. Repeated aspirations provide an excellent means of monitoring the progress of certain disorders, and multiple lymph nodes can be aspirated concurrently to increase the accuracy of the evaluation. Lymph node cytology yields almost as much information as the examination of histologic sections in many disorders (e.g., Hodgkin’s disease, tuberculous lymphadenitis, sarcoidosis, solid metastatic tumors). However, much experience in the interpretation of lymph node smears is necessary for an accurate evaluation. Above all, the examiner must be familiar with the great morphologic diversity of reactive lymph node changes, and therefore particular attention is given to these changes in the present chapter. Four main types of cytologic pattern may be seen on the examination of smears prepared from lymph node aspirate (after Theml 1986): 1. A reactive cellular composition without specific cellular elements. Foci or infections are usually causative, and reactive hyperplasia should be suspected. 2. A reactive cellular composition with specific elements, such as a predominance of epitheloid cells (consistent with sarcoidosis) or Langhans’ cells (consistent with tuberculous lymphadenitis). Hodgkin’s cells and Sternberg cells should raise suspicion of Hodgkin’s disease. 3. A monotonie picture composed of lymphatic cellular elements, consistent with non-Hodgkin’s lymphoma. 4. Cells extrinsic to the lymph node, consistent with metastatic tumor.

Light Microscopic Procedures

The hematologic stain that we use most frequently, and which was used in most of the plates presented in this atlas, is Pappenheim’s panoptic stain. It is based on a combination of the Jenner-May-Grunwald stain and Giemsa stain.

Blood Parasites Principal Causative Organisms of Tropical Diseases

The causative Plasmodium organisms are transmitted to man as sporozoites in the saliva of the feeding anopheles mosquito. The organisms travel in the bloodstream from the capillaries to the liver, where they undergo further development. They enter the liver cells (primary tissue forms) in the “pre-erythrocytic phase” of their life cycle, and after a variable period they are released into the peripheral blood as schizonts. There they attack the erythrocytes in a process which incites episodes of fever. Inside the red cells the schizonts mature through several stages, culminating in the discharge of merozoites from the remains of the erythrocyte; these then proceed to infect fresh erythrocytes. This process takes about 48 h for the parasite of tertian malaria (Plasmodium vivax and Plasmodium ovale) and malignant tertian malaria (Plasmodium falciparum) and 72 h for the parasite of quartan malaria (Plasmodium malariae).

Overview of Cells in the Blood, Bone Marrow, and Lymph Nodes

Figure 1 presents an overview of the various cells of the blood and hematopoiesis. The Figure does not attempt to answer unresolved questions of cell origins and is intended only as an introductory scheme to help the beginner find some order in the bewildering variety of cells.

Techniques of Specimen Collection and Preparation

Differentiation of the peripheral blood is still the most important procedure in the diagnosis of hematologic disorders. The necessary blood smears are usually prepared from venous blood anticoagulated with EDTA (several brands of collecting tube containing EDTA are available commercially). However, many special tests require that the blood be taken from the fingertip or earlobe and smeared directly onto a glass sHde, with no chemicals added. The slide must be absolutely clean to avoid the introduction of artifacts. Slides are cleaned most effectively by degreasing in alcohol for 24 h, drying with a lint-free cloth, and final wiping with a chamois cloth (as a shortcut, the slide may be scrubbed with 96% alcohol and wiped dry).

Immunocytologic Identification and Classification of Lymphoid Malignancies

A combination of morphologic and immunologic approaches to diagnosis often permits a more reliable identification and a more objective classification of malignant lymphoid cells than would be possible using morphologic criteria alone. Examples of this are shown in Figs. 196d, 197, and 198.

Punktionstechnik und Zellpräparation

Die Differenzierung des peripheren Blutes ist auch heute noch ein wichtiges Verfahren in der Diagnostik der Blutkrankheiten. Die dafur notigen Blutausstriche werden meist aus dem mit EDTA versetzten Venenblut angefertigt (bereits vorpraparierte Rohrchen verschiedener Firmen werden im Handel angeboten). Fur zahlreiche SpezialUntersuchungen des Blutausstrichs ist es aber notig, Blut, das aus einer Fingerbeere oder einem Ohrlappchen entnommen ist, direkt (also ohne chemische Zusatze) auf dem Objekttrager auszustreichen. Um verwertbare Praparate zu erhalten, ist darauf zu achten, das nur ganz saubere Objekttrager benutzt werden. Diese erhalt man am besten durch folgendes Vorgehen: Durch 24stundiges Einlegen in Spiritus werden die Objekttrager entfettet, mit einem sauberen Tuch abgetrocknet und mit einem Fensterleder nachgerieben (als Schnellmethode genugt ausnahmsweise ein kraftiges Abreiben mit 96%igem Alkohol und Trockenreiben).

Immunzytologische Differenzierung maligner lymphatischer Erkrankungen

Bei vielen klinischen Fragestellungen erlaubt die Kombination von morphologischer und immunologischer Zelltypisierung eine sicherere Identifizierung und Klassifizierung maligner lymphatischer Zellen, als dies mit ausschlieslich morphologischer Beurteilung moglich ist. Beispiele hierfur werden in Abb. 196d, 197 und 198 illustriert.

General View of Cells in Blood, Bone Marrow and Lymph Nodes

The following plates (Figs. 1 and 2) are intended to provide a survey of the different cells of blood and their hematopoiesis, without commitment on as yet unsolved questions of their genesis. Solely, beginners should be enabled to find some order in the confusing variety of cells and be assisted in becoming familiar with them.

Blood Parasites Most Important Causative Organisms of Tropical Diseases

The causative plasmodia are transmitted to man as sporozoites in the saliva of a biting mosquito. They are carried from the capillaries with the bloodstream to the liver, where they develop further and enter the peripheral blood as schizonts after a variable time. Here they attack the erythrocytes, which clinically triggers the fever. The schizonts mature in the erythrocytes going through different stages. This requires 48 h in the case of (benign) tertian malaria (Plasmodium vivax and Plasmodium ovale), and malignant tertian malaria (Plasmodium falciparum), or 72 h in the case of quartan malaria (Plasmodium malariae). The various stages are encountered in the bloodstream depending on the time of withdrawing the blood (see Figs. 209–213). In addition to the asexual multiplication by division (schizogony), male and female gametocytes serve sexual propagation (sporogony), which however takes place only in the mosquito where two oocysts join. Gametocytes which do not reach a mosquito perish in the human body after about 40 days.