The pus infiltrates the meshes of the cellular tissue, there is sloughing of considerable portions of tissue of low vitality, such as fat, fascia, or tendon, and if the process continues for some time several collections of pus may form.
_Clinical Features._--The reaction in cases of diffuse cellulitis is severe, and is usually ushered in by a distinct chill or even a rigor, while the temperature rises to 103, 104, or 105 F. The pulse is proportionately increased in frequency, and is small, feeble, and often irregular. The face is flushed, the tongue dry and brown, and the patient may become delirious, especially during the night. Leucocytosis is present in cases of moderate severity; but in severe cases the virulence of the toxins prevents reaction taking place, and leucocytosis is absent.
The local manifestations vary with the relation of the seat of the inflammation to the surface. When the superficial cellular tissue is involved, the skin a.s.sumes a dark bluish-red colour, is swollen, dematous, and the seat of burning pain. To the touch it is firm, hot, and tender. When the primary focus is in the deeper tissues, the const.i.tutional disturbance is aggravated, while the local signs are delayed, and only become prominent when pus forms and approaches the surface. It is not uncommon for blebs containing dark serous fluid to form on the skin. The infection frequently spreads along the line of the main lymph vessels of the part (_septic lymphangitis_) and may reach the lymph glands (_septic lymphadenitis_).
With the formation of pus the skin becomes soft and boggy at several points, and eventually breaks, giving exit to a quant.i.ty of thick grumous discharge. Sometimes several small collections under the skin fuse, and an abscess is formed in which fluctuation can be detected.
Occasionally gases are evolved in the tissues, giving rise to emphysema.
It is common for portions of fascia, ligaments, or tendons to slough, and this may often be recognised clinically by a peculiar crunching or grating sensation transmitted to the fingers on making firm pressure on the part.
If it is not let out by incision, the pus, travelling along the lines of least resistance, tends to point at several places on the surface, or to open into joints or other cavities.
_Prognosis._--The occurrence of _septicaemia_ is the most serious risk, and it is in cases of diffuse suppurative cellulitis that this form of blood-poisoning a.s.sumes its most aggravated forms. The toxins of the streptococci are exceedingly virulent, and induce local death of tissue so rapidly that the protective emigration of leucocytes fails to take place. In some cases the pa.s.sage of ma.s.ses of free cocci in the lymphatics, or of infective emboli in the blood vessels, leads to the formation of _pyogenic abscesses_ in vital organs, such as the brain, lungs, liver, kidneys, or other viscera. _Haemorrhage_ from erosion of arterial or venous trunks may take place and endanger life.
_Treatment._--The treatment of diffuse cellulitis depends to a large extent on the situation and extent of the affected area, and on the stage of the process.
_In the limbs_, for example, where the application of a constricting band is practicable, Bier"s method of inducing pa.s.sive hyperaemia yields excellent results. If pus is formed, one or more small incisions are made and a light moist dressing placed over the wounds to absorb the discharge, but no drain is inserted. The whole of the inflamed area should be covered with gauze wrung out of a 1 in 10 solution of ichthyol in glycerine. The dressing is changed as often as necessary, and in the intervals when the band is off, gentle active and pa.s.sive movements should be carried out to prevent the formation of adhesions. After incisions have been made, we have found the _immersion_ of the limb, for a few hours at a time, in a water-bath containing warm boracic lotion or eusol a useful adjuvant to the pa.s.sive hyperaemia.
_Continuous irrigation_ of the part by a slow, steady stream of lotion, at the body temperature, such as eusol, or Dakin"s solution, or boracic acid, or frequent washing with peroxide of hydrogen, has been found of value.
A suitably arranged splint adds to the comfort of the patient; and the limb should be placed in the att.i.tude which, in the event of stiffness resulting, will least interfere with its usefulness. The elbow, for example, should be flexed to a little less than a right angle; at the wrist, the hand should be dorsiflexed and the fingers flexed slightly towards the palm.
Ma.s.sage, pa.s.sive movement, hot and cold douching, and other measures, may be necessary to get rid of the chronic dema, adhesions of tendons, and stiffness of joints which sometimes remain.
In situations where a constricting band cannot be applied, for example, on the trunk or the neck, Klapp"s suction bells may be used, small incisions being made to admit of the escape of pus.
If these measures fail or are impracticable, it may be necessary to make one or more free incisions, and to insert drainage-tubes, portions of rubber dam, or iodoform worsted.
The general treatment of toxaemia must be carried out, and in cases due to infection by streptococci, anti-streptococcic serum may be used.
In a few cases, amputation well above the seat of disease, by removing the source of toxin production, offers the only means of saving the patient.
WHITLOW
The clinical term whitlow is applied to an acute infection, usually followed by suppuration, commonly met with in the fingers, less frequently in the toes. The point of infection is often trivial--a pin-p.r.i.c.k, a puncture caused by a splinter of wood, a scratch, or even an imperceptible lesion of the skin.
Several varieties of whitlow are recognised, but while it is convenient to describe them separately, it is to be clearly understood that clinically they merge one into another, and it is not always possible to determine in which connective-tissue plane a given infection has originated.
_Initial Stage._--Attention is usually first attracted to the condition by a sensation of tightness in the finger and tenderness when the part is squeezed or knocked against anything. In the course of a few hours the part becomes red and swollen; there is continuous pain, which soon a.s.sumes a throbbing character, particularly when the hand is dependent, and may be so severe as to prevent sleep, and the patient may feel generally out of sorts.
If a constricting band is applied at this stage, the infection can usually be checked and the occurrence of suppuration prevented. If this fails, or if the condition is allowed to go untreated, the inflammatory reaction increases and terminates in suppuration, giving rise to one or other of the forms of whitlow to be described.
_The Purulent Blister._--In the most superficial variety, pus forms between the rete Malpighii and the stratum corneum of the skin, the latter being raised as a blister in which fluctuation can be detected (Fig. 9, a). This is commonly met with in the palm of the hand of labouring men who have recently resumed work after a spell of idleness.
When the blister forms near the tip of the finger, the pus burrows under the nail--which corresponds to the stratum corneum--raising it from its bed.
There is some local heat and discoloration, and considerable pain and tenderness, but little or no const.i.tutional disturbance. Superficial lymphangitis may extend a short distance up the forearm. By clipping away the raised epidermis, and if necessary the nail, the pus is allowed to escape, and healing speedily takes place.
_Whitlow at the Nail Fold._--This variety, which is met with among those who handle septic material, occurs in the sulcus between the nail and the skin, and is due to the introduction of infective matter at the root of the nail (Fig. 9, b). A small focus of suppuration forms under the nail, with swelling and redness of the nail fold, causing intense pain and discomfort, interfering with sleep, and producing a const.i.tutional reaction out of all proportion to the local lesion.
To allow the pus to escape, it is necessary, under local anaesthesia, to cut away the nail fold as well as the portion of nail in the infected area, or, it may be, to remove the nail entirely. If only a small opening is made in the nail it is apt to be blocked by granulations.
[Ill.u.s.tration: FIG. 9.--Diagram of various forms of Whitlow.
a = Purulent blister.
b = Suppuration at nail fold.
c = Subcutaneous whitlow.
d = Whitlow in sheath of flexor tendon (e). ]
_Subcutaneous Whitlow._--In this variety the infection manifests itself as a cellulitis of the pulp of the finger (Fig. 9, c), which sometimes spreads towards the palm of the hand. The finger becomes red, swollen, and tense; there is severe throbbing pain, which is usually worst at night and prevents sleep, and the part is extremely tender on pressure.
When the palm is invaded there may be marked dema of the back of the hand, the dense integument of the palm preventing the swelling from appearing on the front. The pus may be under such tension that fluctuation cannot be detected. The patient is usually able to flex the finger to a certain extent without increasing the pain--a point which indicates that the tendon sheaths have not been invaded. The suppurative process may, however, spread to the tendon sheaths, or even to the bone. Sometimes the excessive tension and virulent toxins induce actual gangrene of the distal part, or even of the whole finger. There is considerable const.i.tutional disturbance, the temperature often reaching 101 or 102 F.
The treatment consists in applying a constriction band and making an incision over the centre of the most tender area, care being taken to avoid opening the tendon sheath lest the infection be conveyed to it.
Moist dressings should be employed while the suppuration lasts. Carbolic fomentations, however, are to be avoided on account of the risk of inducing gangrene.
_Whitlow of the Tendon Sheaths._--In this form the main incidence of the infection is on the sheaths of the flexor tendons, but it is not always possible to determine whether it started there or spread thither from the subcutaneous cellular tissue (Fig. 9, d). In some cases both connective tissue planes are involved. The affected finger becomes red, painful, and swollen, the swelling spreading to the dorsum. The involvement of the tendon sheath is usually indicated by the patient being unable to flex the finger, and by the pain being increased when he attempts to do so. On account of the anatomical arrangement of the tendon sheaths, the process may spread into the forearm--directly in the case of the thumb and little finger, and after invading the palm in the case of the other fingers--and there give rise to a diffuse cellulitis which may result in sloughing of fasciae and tendons. When the infection spreads into the common flexor sheath under the transverse carpal (anterior annular) ligament, it is not uncommon for the intercarpal and wrist joints to become implicated. Impaired movement of tendons and joints is, therefore, a common sequel to this variety of whitlow.
The _treatment_ consists in inducing pa.s.sive hyperaemia by Bier"s method, and, if this is done early, suppuration may be avoided. If pus forms, small incisions are made, under local anaesthesia, to relieve the tension in the sheath and to diminish the risk of the tendons sloughing. No form of drain should be inserted. In the fingers the incisions should be made in the middle line, and in the palm they should be made over the metacarpal bones to avoid the digital vessels and nerves. If pus has spread under the transverse carpal ligament, the incision must be made above the wrist. Pa.s.sive movements and ma.s.sage must be commenced as early as possible and be perseveringly employed to diminish the formation of adhesions and resulting stiffness.
_Subperiosteal Whitlow._--This form is usually an extension of the subcutaneous or of the thecal variety, but in some cases the inflammation begins in the periosteum--usually of the terminal phalanx.
It may lead to necrosis of a portion or even of the entire phalanx. This is usually recognised by the persistence of suppuration long after the acute symptoms have pa.s.sed off, and by feeling bare bone with the probe.
In such cases one or more of the joints are usually implicated also, and lateral mobility and grating may be elicited. Recovery does not take place until the dead bone is removed, and the usefulness of the finger is often seriously impaired by fibrous or bony ankylosis of the interphalangeal joints. This may render amputation advisable when a stiff finger is likely to interfere with the patient"s occupation.
SUPPURATIVE CELLULITIS IN DIFFERENT SITUATIONS
_Cellulitis of the forearm_ is usually a sequel to one of the deeper varieties of whitlow.
In the _region of the elbow-joint_, cellulitis is common around the olecranon. It may originate as an inflammation of the olecranon bursa, or may invade the bursa secondarily. In exceptional cases the elbow-joint is also involved.
Cellulitis of the _axilla_ may originate in suppuration in the lymph glands, following an infected wound of the hand, or it may spread from a septic wound on the chest wall or in the neck. In some cases it is impossible to discover the primary seat of infection. A firm, brawny swelling forms in the armpit and extends on to the chest wall. It is attended with great pain, which is increased on moving the arm, and there is marked const.i.tutional disturbance. When suppuration occurs, its spread is limited by the attachments of the axillary fascia, and the pus tends to burrow on to the chest wall beneath the pectoral muscles, and upwards towards the shoulder-joint, which may become infected. When the pus forms in the axillary s.p.a.ce, the treatment consists in making free incisions, which should be placed on the thoracic side of the axilla to avoid the axillary vessels and nerves. If the pus spreads on to the chest wall, the abscess should be opened below the clavicle by Hilton"s method, and a counter opening may be made in the axilla.
Cellulitis of the _sole of the foot_ may follow whitlow of the toes.
In the _region of the ankle_ cellulitis is not common; but _around the knee_ it frequently occurs in relation to the prepatellar bursa and to the popliteal lymph glands, and may endanger the knee-joint. It is also met with in the _groin_ following on inflammation and suppuration of the inguinal glands, and cases are recorded in which the sloughing process has implicated the femoral vessels and led to secondary haemorrhage.
Cellulitis of the scalp, orbit, neck, pelvis, and perineum will be considered with the diseases of these regions.
CHRONIC SUPPURATION
While it is true that a chronic pyogenic abscess is sometimes met with--for example, in the breast and in the marrow of long bones--in the great majority of instances the formation of a chronic or cold abscess is the result of the action of the tubercle bacillus. It is therefore more convenient to study this form of suppuration with tuberculosis (p. 139).
SINUS AND FISTULA
#Sinus.#--A sinus is a track leading from a focus of suppuration to a cutaneous or mucous surface. It usually represents the path by which the discharge escapes from an abscess cavity that has been prevented from closing completely, either from mechanical causes or from the persistent formation of discharge which must find an exit. A sinus is lined by granulation tissue, and when it is of long standing the opening may be dragged below the level of the surrounding skin by contraction of the scar tissue around it. As a sinus will persist until the obstacle to closure of the original abscess is removed, it is necessary that this should be sought for. It may be a foreign body, such as a piece of dead bone, an infected ligature, or a bullet, acting mechanically or by keeping up discharge, and if the body is removed the sinus usually heals. The presence of a foreign body is often suggested by a ma.s.s of redundant granulations at the mouth of the sinus. If a sinus pa.s.ses through a muscle, the repeated contractions tend to prevent healing until the muscle is kept at rest by a splint, or put out of action by division of its fibres. The sinuses a.s.sociated with empyema are prevented from healing by the rigidity of the chest wall, and will only close after an operation which admits of the cavity being obliterated.
In any case it is necessary to disinfect the track, and, it may be, to remove the unhealthy granulations lining it, by means of the sharp spoon, or to excise it bodily. To encourage healing from the bottom the cavity should be packed with bis.m.u.th or iodoform gauze. The healing of long and tortuous sinuses is often hastened by the injection of Beck"s bis.m.u.th paste (p. 145). If disfigurement is likely to follow from cicatricial contraction--for example, in a sinus over the lower jaw a.s.sociated with a carious tooth--the sinus should be excised and the raw surfaces approximated with st.i.tches.
The _tuberculous sinus_ is described under Tuberculosis.