symptoms gradually subsiding, and passing into a less violent but
persistent type. In other cases the disease assumes this form from the
beginning, and such instances are more commonly noted after ordinary
bronchitis of moderate severity or after whooping cough. In adults this
form also is less common than in children. It is met with as an
intercurrent affection in certain cases of phthisis; and not rarely the
exacerbations of that disease are due to the development of centres of
catarrhal pneumonia which too often become later the seat of an
extension of the tuberculous process. It occurs in this form also in
the old and cachectic, and doubtless proves the undetected source of
death in many cases where the end is preceded by irregular pains and by
some signs of hypostatic infiltration of the lungs. In a feeble and
exhausted state of the system at all ages it is liable to be induced.
At times this is brought about by a series of recurring slight
catarrhal attacks, gradually deepening into a subacute process of
catarrhal pneumonia; while in other cases a more powerful disturbing
cause will in such states of system directly induce this type of the
disease. It develops insidiously. There is little or no pain. The fever
is highly irregular; the maxima usually occur in the evening and reach
102° or 103°, but there may be such marked remissions as to make the
case closely simulate one of intermittent malarial fever complicated
with bronchitis, and I have known such an error to be made in repeated
instances. In some cases, especially in the old and feeble, there may
be very little fever, at least until the disease is more fully
developed. The dyspnoea is not urgent; the pulse is not extremely
rapid; and cough may actually seem diminished if the disease has
originated in the course of severe bronchitis. The physical signs
develop slowly, but may eventually appear over considerable areas of
lung-tissue. In this way with an irregular fluctuating pyrexia,
presenting from time to time marked exacerbations, with an equally
varying amount of cough and muco-purulent expectoration, and with
marked and progressive debility and emaciation, these forms of
catarrhal pneumonia pursue a course extending over many weeks or
months. Complete recovery is still possible, after a tedious
convalescence. Commonly, {364} however, some permanent lesion of the
lungs, as emphysema, dilatation of the bronchial tubes, or
circumscribed induration of the lung, will remain as sequels. In a
large proportion of cases a fatal result finally follows, more commonly
from the passage of the morbid process into pulmonary phthisis usually
associated with true tuberculosis; while in some cases acute miliary
tuberculosis supervenes and proves rapidly fatal. Undoubtedly, however,
cases of chronic catarrhal pneumonia may continue purely as such, with
recurring exacerbations at irregular intervals from the development of
new centres of disease, until death is finally induced by exhaustion.
COMPLICATIONS AND SEQUELS.--It is needless to repeat what has been said
as to the essential connection between catarrhal pneumonia and
bronchitis, so that the latter is to be regarded as an invariable
symptom and attendant rather than as a complication. As might be
expected also, catarrhal laryngitis of varying degrees of severity is
of comparatively common occurrence. Especially in cases occurring in
connection with measles, where the upper respiratory tract is already
inflamed, the increased intensity of the laryngitis may induce so much
swelling as to cause some mechanical obstruction to respiration which
will arouse fears of pseudo-membranous formation, and which, during the
spasms of cough and dyspnoea which are apt to occur occasionally, will
closely simulate true croup. Pleurisy rarely appears in such a high
degree as to constitute a serious complication. When the areas affected
are superficial, there is apt to be circumscribed plastic exudation on
the corresponding portions of the pleura. Less frequently quite
extensive plastic pleurisy occurs, with layers of exudation
sufficiently thick to modify the physical signs; and in still more rare
instances does fibro-serous effusion occur. I have noted the occurrence
of purulent pleurisy, as has Jürgensen; and in two cases it was found
to be associated with subpleural purulent foci, one at least of which
had ruptured. In the other cases the purulent character of the pleurisy
was presumably due to the constitutional dyscrasia. Allusion has
already been made to the occurrence of emphysema and bronchiectasis in
connection with catarrhal pneumonia, especially of the subacute and
chronic varieties. The observations of Delafield on the tendency of the
catarrhal inflammatory process to extend laterally through the
bronchial wall into the peribronchial zones of lung-tissue are of
special interest in their bearing on the liability to dilatation of the
bronchial tubes and to deep-seated circumscribed indurations of
lung-tissue as sequels of catarrhal pneumonia.
Gangrene of the lung I have known to occur as a complication in one
case of extraordinary severity, but in which recovery ultimately
followed a very tedious process of reparation. It was attended with
recurring attacks of hæmoptysis. The case occurred in a young man of
twenty-four years of age: the lesions existed chiefly over the right
back, though there were smaller centres elsewhere; and the spot of
gangrene and from which the hemorrhages occurred was near the right
root. He was four months in bed; his convalescence extended over a
year; evidences of induration at the above spot lasted five years; and
now, eight years after the attack, he is in vigorous health, though
still with slight cough.
Pneumothorax may occur as a sequel in protracted cases in consequence
of the rupture of a subpleural abscess. I have elsewhere reported cases
of this, and Steffen has also reported two instances.
Tuberculosis occurs in various ways in connection with catarrhal
pneumonia. There may be a development of acute general miliary
tuberculosis, owing to the depressing and irritating effect of the
disease upon a constitution strongly predisposed to tuberculosis. Or
tuberculous pulmonary phthisis may ensue, either directly as a
complication or as a sequel to ulcerative changes of inflammatory
nature in the lung. Finally, those who have passed through {365} an
attack of catarrhal pneumonia are usually left with such vulnerability
of system that any predisposition to phthisis or to tuberculosis is
very apt to be readily called into activity. It seems highly important
to note this close and complicated connection between catarrhal
pneumonia, in its various types and even in its mild and circumscribed
form, and subsequent organic disease.
Further evidence of the profound disturbance of nutrition often
effected by an attack of this disease may be found in the occasional
development of marked rachitis, and in the much more frequent
establishment of subsequent anæmia and debility, which prove obstinate
and are associated with a high degree of susceptibility of the system
to morbid influences, and which are doubtless, in some instances at
least, dependent upon impaired primary assimilation due to lesions of
the intestinal canal, which existed as complications of the original
attack of catarrhal pneumonia. It has been mentioned that
gastro-intestinal irritation is often present, both in the acute and in
the more chronic forms, and this may reach such a high degree as to
justify the name of a complication. It has seemed to be especially in
these cases, or in those where, owing to the subsequent vulnerability
of the system, gastro-intestinal catarrh occurs as a sequel, that the
serious impairment of nutrition above mentioned is most likely to
ensue.
Lastly, allusion must be made to the frequency with which severe
nervous symptoms appear, especially during the later stage of the
attack. As has been seen, convulsions are not rare in children, while
at all ages active delirium and extreme restlessness, often requiring
restraint, are of frequent occurrence. These cannot be attributed, as a
rule, to uræmic intoxication, but are to be referred to the high
systemic irritation, the great nervous exhaustion, and the marked
interference with respiration and aëration of the blood. It is probable
also that circumscribed areas of lepto-meningitis, or even of
tuberculous meningitis, are of occasional occurrence in these cases.
DIAGNOSIS.--The direct recognition of catarrhal pneumonia in its acute
stage is not always free from difficulty, while both in the acute and
chronic forms there are certain conditions with which care must be used
not to confound it.
In the first place, it is important to recognize at the earliest moment
the development of the pneumonic process during acute bronchitis of the
finer tubes. In all cases of the latter, especially in children and in
patients of debilitated system, this occurrence must be constantly
apprehended. Its occurrence may be strongly suspected if sudden rise in
the fever and in the rate of respiration and pulse is noted, though if
the areas affected are small, scattered, or deeply seated it may not at
first be possible to demonstrate it. It must be remembered also that in
the capillary bronchitis of children the fever and disturbance of pulse
and respiration may be aggravated quite abruptly from extensions of the
disease, so that actually it must be recognized that in such cases the
presence of small pneumonic centres can only be assumed, but can
neither be proved nor disproved. The course of the pyrexia may afford
some assistance, since I believe more marked diurnal variations,
amounting at times to distinct remissions, will be noted in cases of
catarrhal pneumonia than in those of severe bronchitis not so
complicated. In adults less hesitation need be felt in admitting the
development of pneumonic foci under such circumstances, even though the
physical signs are negative. Usually, however, carefully repeated
examination will soon reveal the signs of infiltration in irregularly
disposed areas; and I suspect it must be infrequent that the close
study of the relative physical signs afforded by examination of the
corresponding areas on the two sides of the chest will not afford
substantial ground for diagnosis.
It must always be remembered that areas of consolidation arising in the
{366} course of severe bronchitis of the finer tubes may be from
collapse, and not from pneumonia. This is especially apt to be the case
in children, but occurs not rarely in feeble adults. The diagnosis of
catarrhal pneumonia from mere collapse must therefore be carefully
considered. The occurrence of collapse, though it may be marked by
sudden and severe increase of dyspnoea, pulse-rate, and distress, is
not accompanied by a corresponding rise of temperature; and this is a
point of capital importance. Again, the development of the physical
signs is usually much more abrupt than where catarrhal pneumonia is
occurring. Considerable areas of dulness on percussion appear in the
course of twelve or twenty-four hours, between the successive visits of
the physician, without corresponding increase of fever; and these areas
may subsequently present marked peculiarities, at times disappearing
almost as abruptly, to be succeeded by similar areas in other portions
of the lungs, though at times also they persist and pass through the
changes already described. The physical signs furnish further
assistance. Retraction of the base of the chest during inspiration is
much more common in collapse, especially when the areas are at all
extensive and when they occur in the lower lobes, since there is
necessarily a reduction in the volume of the lungs; and this, added to
the inability to inflate the affected lobules, induces this important
sign, which should always be carefully looked for. The dulness over
collapsed lung-tissue is rarely as marked as over extensive areas of
catarrhal pneumonia; the vocal resonance and fremitus are diminished;
râles are wanting or are feeble and transmitted; and again, it must be
mentioned that the physical signs present remarkable variations within
short periods of time. It is, however, necessary to suspect the
existence of pneumonic areas in cases of severe bronchitis where
portions of lung become collapsed, and continue so, while the general
symptoms indicate persistence of inflammatory action. The differential
diagnosis is therefore in many instances rather as to the relative
proportion of these factors than as to the total absence of either.
Catarrhal may be confounded with croupous pneumonia. This error may
most readily be made if the case be not seen until a consolidated area
of considerable extent is present, since, as we have seen, in some
instances the foci of catarrhal pneumonia may chiefly occupy one lung
and may coalesce. Even then, however, the dulness of percussion rarely
corresponds with the outline of the lobe, and is rarely as complete as
in croupous pneumonia, nor are the bronchial respiration, the
bronchophony, and the exaggerated vocal fremitus as pronounced, for the
simple reason that the consolidation is not so uniform, and that many
of the smaller bronchial tubes are more or less obstructed by swelling
of the mucous membrane or by the accumulation of viscid secretions. It
will rarely happen, moreover, that strong efforts at
respiration--induced, if necessary, by having the patient cough during
the auscultation, so as to ensure a full inspiration--will fail to
develop subcrepitant râles at some point of the catarrhal
consolidation. To this must be added the information drawn from the
history of the case; the character of the cough and sputa; and, above
all, the atypical course of the pyrexia, and the fact that
carefully-repeated examinations will show frequent and abrupt
variations in the physical signs around the margins of the affected
area. If the case is observed during its development, there will be
less difficulty in making a correct diagnosis. The process is very
rarely unilateral throughout its development; and the evident
bronchitis, the development of irregularly scattered foci of partial
consolidation in both lungs, and the frequent coexistence of collapse,
combined with the absence of the characteristic symptoms and course of
the croupous form, make the nature of the case apparent.
The diagnosis of ordinary pleurisy with effusion from catarrhal
pneumonia presents no difficulty. But, on the other hand, it is not
easy to recognize the {367} occurrence of a moderate pleuritic effusion
complicating a catarrhal pneumonia. The fact that the lower lobes of
both lungs are apt to be involved in the pneumonic process interferes
with the displacement of the heart, and the enfeebling of the
respiratory and vocal phenomena may be attributed to bronchial
obstruction or to collapse. A careful study of the outline of the dull
area, and of the effect upon it of changes in the position of the
patient's body, has proved of service. After all, this is a rare
complication; but not so rare is the coexistence of plastic pleurisy
with catarrhal pneumonia, and this also may give rise to doubt in the
diagnosis. An area of dulness appearing near the base and extending
with moderate rapidity, attended with bronchial irritation, with
irregular fever of slight or of moderate degree, and with some
evidences of engorgement of the lower part of the opposite lung, and
presenting over the affected area, in addition to marked percussion
dulness, bronchial respiration not of intense concentrated type,
distant bronchophony, no increase of vocal fremitus, and crackling
râles irregularly scattered over the affected area, represent a
clinical condition, occasionally met with in adults, which requires
care to ensure its proper interpretation. I have observed crackling
râles in particular in such cases, which might have been regarded
either as intrapleural or as developed in the finest bronchioles. It
will be observed, however, that the degree of dulness is excessive for
a mere plastic pleurisy; that the respiratory and vocal signs, while
not typical of croupous consolidation, are yet far more developed than
would be consistent with the presence of a quantity of plastic pleural
exudation sufficient to cause such dulness; that any such grade of
plastic pleurisy is very rare; and that the general symptoms and the
course of the disease are indicative of much more gravity than would
attach to such a pleuritic process if it were to exist. It is
altogether probable that there has been here a coexistence of catarrhal
pneumonia with a moderate degree of plastic exudation on the
corresponding part of the pleura.
Again, it is essential to distinguish catarrhal pneumonia from acute
miliary tuberculosis with special localization in the lungs and
meninges. This diagnosis may present marked difficulties both in
children and in adults, but of course chiefly in the former, and
especially at a late period of the case, when cerebral symptoms,
closely simulating those characteristic of tubercular meningitis, may
have appeared. The irregular fever, the marked disturbance of pulse and
respiration, with evidence of diffuse bronchial irritation, but out of
proportion to the physical signs of consolidation, the occasional
vomiting in the early stage, and the appearance of nervous symptoms,
are present in both conditions. But in tuberculosis there may be high
fever before any marked evidences even of bronchial irritation appear;
there is not so much bronchitis to aid in explaining the dyspnoea;
there is not so much tendency to pulmonary collapse, and the physical
signs present are more persistent; the pulse presents the
characteristic successive stages of alteration; vomiting is apt to be
more frequent, while the diarrhoea which is often present in catarrhal
pneumonia is replaced by constipation; the Cheyne-Stokes respiration is
more apt to appear; and, finally, an ophthalmoscopic examination may
reveal retinal tubercles. It remains true, however, that in some cases
it must evidently be wellnigh impossible to decide whether the case is
one of acute tuberculosis, with a high grade of bronchitis, and very
probably with some centres of pneumonic infiltration associated, or one
of catarrhal pneumonia developing out of a severe bronchitis. It must
be remembered, moreover, that even when the case has begun as one of
catarrhal pneumonia there is a tendency to the development of
tuberculosis, both pulmonary and general; so that it may be found after
death that the nervous symptoms, which were reasonably ascribed to
congestion, to high temperature, to prolonged and exhausting nervous
irritation, and to the effect of imperfectly aërated blood, are in
reality connected with the {368} presence of miliary tubercles in the
meninges, while at the same time these have also been developing around
the pneumonic foci in the lungs.
It is no less important to bear in mind the necessity for close study
in distinguishing between chronic catarrhal pneumonia and phthisis.
There are not a few cases of the former where the protracted irregular
fever of hectic type, the progressive debility and emaciation, the
moist râles, the areas of altered percussion resonance, possibly the
signs of a dilated bronchus, and the purulent sputa, may closely
simulate true phthisis, but yet which microscopic examination of the
sputa for bacilli and elastic fibre, and the effect of treatment and
climatic change, prove to be merely inflammatory. On the other hand, it
appears undoubted, from the standpoint of clinical observation, that in
many cases, especially where a predisposition exists, catarrhal
pneumonia terminates in phthisis.
DURATION, TERMINATIONS, PROGNOSIS.--The duration of this disease is
highly irregular, and care must be taken not to confound the subsidence
of the marked general symptoms with a full restoration of the affected
areas. A considerable period is required for this latter process to be
effected, and during this interval the lung-tissue continues in a
highly sensitive and vulnerable state. Speaking with reference to the
obvious symptoms, however, it may be said that mild acute cases may
terminate in seven to ten days; fully-developed acute cases, in fifteen
to twenty-five days; while the subacute and chronic forms may last
several or many months.
Death may occur in from two to four days, especially in weak young
children, while more commonly the fatal result occurs from the seventh
to the tenth day. Of course in the chronic form death may occur after
many weeks or months.
The various terminations are in complete recovery; in apparent
recovery, but with vulnerable lungs or general system; in partial
recovery, but with residual lesions, such as bronchial dilatation or
emphysema; or the disease may pass into the chronic form, associated
with chronic bronchitis, or it may lead to the development of acute
tuberculosis or of chronic phthisis.
The rate of mortality of catarrhal is much higher than that of croupous
pneumonia. Excluding the mild circumscribed form, if such is admitted
to exist, as I believe it does, the mortality varies from 30 to 60 per
cent. It is apparently less fatal when occurring in the course of
measles than in connection with some other diseases, as diphtheria or
whooping cough. The nature and tendencies of this disease make it
evident that debility and frailty of the patient would render catarrhal
pneumonia much more fatal. So it is found that in infants within the
year death almost constantly follows, and in older children of bad
constitution, especially in those who are scrofulous or rachitic and
subjected to malhygienic influences, it is almost equally fatal. After
puberty the mortality is chiefly influenced by the constitutional state
of the subject and by the extent of the pneumonic process.
The greater tendency to pulmonary collapse and to severe capillary
bronchitis in young children justifies Jürgensen's generalization, that
before the age of puberty the danger from catarrhal pneumonia grows
greater in proportion to the youth of the individual. Partly because
the disease is more apt to assume the subacute form in feeble and
sickly individuals, partly because in this form the pneumonic process
is more apt to run into destructive lesions of the lung-tissue or to
induce tuberculosis, it is found that the mortality from the subacute
is even greater than from the ordinary acute form.
It is needless to detail the special symptoms of unfavorable
significance. The most important considerations to guide us in
prognosis are, therefore, the age, constitution, and vital resistance
of the individual; the extent of the pneumonia and of the associated
pulmonary collapse and capillary bronchitis; the degree of
gastro-intestinal irritation; the vigor of the circulation {369} and
respiration, and the manner in which aëration of the blood is
maintained; and, finally, the grade of the fever and the character of
the nervous symptoms.
TREATMENT.--It is difficult to lay down definite rules for the
treatment of catarrhal pneumonia, as the indications are extremely
variable and complicated.