Peritonitis in Geriatric Inpatients MAREK WROBLEWSKI, PAWEL MIKULOWSKI

Summary Of 212 cases of peritonitis found in a retrospective study of geriatic inpatients, the most common causes were mesenteric infarction, malignancy, intestinal obstruction, perforated peptic ulcer, cholecystitis, diverticulitis and perforation of the urinary bladder. The diagnostic accuracy was 47%. Abdominal pain had been observed in only 55% of the cases, and guarding and/or abdominal rigidity in only 34%. Other findings such as tachycardia and fever were more common, but the specificities of these signs were low.

Introduction Early diagnosis of peritonitis is the key to good outcome, particularly among geriatric patients. This demands familiarity with the typical modes of presentation of peritonitis. Although a vast body of literature on the acute abdomen already exists, there have been few studies dealing with peritonitis in elderly people. The use of conventional diagnostic criteria, based on findings from studies of younger individuals, may be a source of serious diagnostic error in geriatric medicine. As reported by Cope [1], diagnosis of peritonitis is facilitated by grouping the symptoms as reflex or toxic. According to several sources [ 1 5], the most consistent symptom of peritonitis is pain and the most predominant sign is involuntary reflex rigidity of the abdomen. The aims of this study were to estimate the prevalence and diagnosis of peritonitis in a clinic for long-term care medicine. Methods Varnhem Hospital at Malmo in southern Sweden, where this investigation was performed, is a geriatric teaching hospital with about 1000 inpatients. During the study period, a third of the beds were allotted for geriatric rehabilitation. Two-thirds of the patients were in long-stay wards for the chronically disabled unable to live at home.

Of 9585 patients who died at the hospital during a 20-year period (1968-87), 7668 (80%) came to autopsy and all the records were available for study. During the same period, 290 patients were referred from Varnhem Hospital to the Department of Surgery at Malmo General Hospital for a variety of reasons, mainly suspected abdominal emergency. The referred cases were identified retrospectively from the hospital record system. In accordance with hospital rules, all suspected abdominal emergencies were referred to the department of surgery. In all, 212 cases of peritonitis were found (144 women and 68 men, mean age 82, range 60-99 years). In 164 cases not referred to the'Department of Surgery, diagnosis was made at autopsy, and, of 48 cases identified in the 290 patients referred to the Department of Surgery, diagnosis was made at laparotomy in 14 cases and at autopsy in 34. The autopsy criterion of peritonitis was the presence of fibrinous exudate, more or less adherent to the peritoneal serosa, with or without other inflammatory fluids. At autopsy reports, distinction was made between localized and diffuse peritonitis. Peritoneal abscess was reported as a separate entity, which might occur in association with peritonitis of either type. Approximately 90% of autopsies had been performed by the same senior pathologist. Of 212 cases of peritonitis, 46 were patients on narcotic drug treatment for other reasons than peritonitis, leaving 166 to be included in studies of symptomatology (the case group). For comparison of frequencies of symptoms and signs, and for computations of specificity, a control group (n = 166) was chosen. Each patient in the case group was allotted a Age and Ageing 1991.20:90-94

PERITONITIS IN GERIATRIC INPATIENTS control matched for sex and age (± 3 years), but without peritonitis, and not on narcotic drug treatment. Symptoms and signs during the 3 days preceding death or laparotomy were studied retrospectively from the complete hospital records. The y} test was used for statistical analysis of the data, p values greater than 0.05 being considered non-significant.

Results The prevalence at death of peritonitis among the autopsied geriatric inpatients was 2.6%. The causes of peritonitis in 212 cases are presented in Table I. The most common cause of peritonitis was mesenteric infarction (20%). Perforations of internal organs were also fre-

Table I. Causes and diagnostic accuracy in 212 cases of peritonitis No.

of cases

Diagnostic 0 /"• /"* 1 ii*>] i".\

1

dLLUrdCV

Cause of peritonitis

n

Mesenteric infarction Malignancy Intestinal obstruction with perforation Perforated peptic ulcer Cholecystitis with perforation Diverticulitis with perforation Perforation of the urinary bladder Others Total

0/

/o

/o

42 28 27 26 22 19 19 29

20 13 13 12 10 9 9 14

55 54 67 42 45 47 21 31

212

100

47

Table II. Diagnostic accuracy in 212 cases of peritonitis, by patient characteristics

Characteristics Patients with narcotic drugs treatment (n = 46) No narcotic drugs (n = 166) Diabetics (n = 23) Non-diabetics (n=189) Patients with malignancy (n = 60) No malignancy (n = 152) Women (n = 144) Men(n = 68) Diffuse peritonitis (n = 136) Localized peritonitis (n = 76) Age 80 (n = 75) Age 81 (n=137)

Diagnostic accuracy (%) "

P values (y.2)

28) 52/

0.005

30 | 49/

0.098

401 49/

0.219

49 1 43/

0.417

46 1 49/

0.665

48 1 46 1

0.779

M. WROBLEWSKI, P. MIKULOWSKI Table III. Combinations of the symptoms and signs with the highest values for specificity Combinations of symptoms and signs

Sensitivity

Specificity

Abdominal pain Nausea/vomiting } Tachycardia

0 34

0.93

Abdominal pain Fever } Tachycardia

0.40

0.92

Nausea/ vomiting Tachycardia } Fall of blood pressure

0.30

0.90

Nausea/vomiting ) Fever > Tachycardia J

%M

6,M

quent. Of the total of 19 cases with perforated urinary bladders, 15 had occurred during the first 10 years of the 20-year period studied, and all 19 patients had had indwelling catheters. Among the 29 cases of peritonitis due to other causes, the commonest finding was renal abscess (n = 10). Diagnostic accuracy was poor, acute abdomen having been suspected or peritonitis correctly diagnosed in only 99 (47%) of the 212

cases. There were no differences in diagnostic accuracy between age groups or the sexes or between the diffuse and localized peritonitis categories. Although diagnostic accuracy was significantly poorer among patients on narcotherapy, none the less it was poor (52%) even among those not on narcotherapy (Tables I and II). With regard to symptomatology, among those not on narcotic drug treatment there were no significant differences in the occurrence of signs and symptoms between the localized and diffuse peritonitis categories. Abdominal pain occurred in only 55% of patients with peritonitis (and the level of diagnostic accuracy was higher among these patients, 80%). Fever ( > 37.0°C) and tachycardia ( > 100 beats/min) were more common, but these symptoms had low specificity. There were no cases of absolutely silent peritonitis The frequencies of symptoms and signs are presented in the Figure. As there were no single symptoms or signs with high values of both for sensitivity and specificity, the different combinations were studied. Table III shows the four combinations with the highest value for specificity, though unfortunately, as expected, the sensitivities of these combinations were very low. Physical examination of the abdomen was recorded in 115 of 166 patients with peritonitis. Guarding and/or abdominal rigidity was found in only 34% (Table IV). The fatality in perito-

100

E2i Peritonitis D Control group

80" 6040-

NS

20-

Tachycardia

Fever

Nausea/ vomiting

Abdominal pain

Fall of blood pressure

Rest dyspnoea

Inability to pass faeces or flatus

Figure. Prevalence of symptoms and signs in geriatric inpatients with peritonitis and control group (•**p< 0.001; NS = non-significant)

PERITONITIS IN GERIATRIC INPATIENTS

93

Table IV. Findings at examination of the abdomen, and diagnostic accuracy

Findings Tenderness Guarding or rigidity Distension Diminished or absent bowel sounds

Diagnostic accuracy in cases with definite findings

Total no. examined

Frequency of definite findings (°'o)

115 115 115

73 34 69

92 92 77

96

52

96

nitis was high, only nine (4%) of 212 patients surviving. The characteristics of the survivors were as follows: average age 81 years; absence of narcotherapy; presence of abdominal pain; and, in six of the nine cases, presence of abdominal rigidity.

Discussion To the best of our knowledge, this study is unique in as much as it deals with a large series of elderly patients with peritonitis at a geriatric teaching hospital with a high autopsy rate, 80%. The prevalence of peritonitis among autopsied geriatric inpatients was 2.6%. The most common cause was mesenteric infarction. There have been several reports on mesenteric infarction in elderly patients [6-9], in all of which fatality was found to be high. Perforation of internal organs was found to be a common cause of peritonitis (40%), perhaps partly because of the high frequency among elderly patients of ulcer disease [10-14] and diverticulitis [15, 16] presenting with only vague features and therefore subject to delayed diagnosis and treatment. A large proportion of cases of peritonitis due to perforation of the urinary bladder can be explained by the common use of indwelling catheters during the 1960s and 1970s. The risk of bladder perforation has been discussed previously by others [17, 18]. Acute appendicitis has been reported as a cause of peritonitis in the elderly [19-21], though only five cases were found in this study.

(%)

This investigation revealed an accuracy in the diagnosis of peritonitis of only 47%. Diagnostic accuracy was poorest among patients on narcotic drug treatment. However, this factor alone is insufficient to explain the diagnostic failures. Peritonitis may also be difficult to recognize in cases where the clinical manifestations are masked due to corticosteroid treatment [22] but only two patients in this study had been on steroid therapy. A possible explanation of the low level of diagnostic accuracy may be the absence of symptoms and signs with both high sensitivity and specificity. Abdominal pain occurred in only 50%. Cutaneous and, probably, also visceral pain sensitivity decreases with age [23], and might explain the lack of pain, in gut perforation [12, 14, 24] as in myocardial infarction [25, 26]. Another possible explanation is the overshadowing of abdominal pain by other severe diseases, as many of the patients in this study were seriously ill. A characteristic of this study is the frequent absence of definite findings at physical examination of the abdomen, a particularly important feature being the lack of guarding and rigidity, an absence possibly to be explained as an effect of muscular atonia. Physical examination of the abdomen had been recorded in only 11 5 of the 166 patients of the case group in this retrospective study, the lack of examinations possibly having been due to the absence of suspicions of abdominal emergency in many cases. In view of the uncertainties in applying data obtained in a retrospective study, mainly based

94

M. WROBLEWSKI, P MIKULOWSKI

on deceased patients, to clinical practice, it is desirable to find other means of studying abdominal emergencies in elderly patients.

16.

References

17.

1. Cope Z, ed. The early diagnosis of the acute abdomen. Oxford: Oxford University Press, 1951;233-43. 2. Bender MD, Ockner RK. Diseases of the peritoneum. In: Sleisenger MH, Fordtran JS, ed. Gastrointestinal disease. Philadelphia, PA: VV. B. SaundersCo., 1983;1569-91. 3. Isselbacher KJ, La Mont JT. Diseases of the peritoneum and mesentery. In: Thorn GW, Adams RD, Braunwald E, Isselbacher KJ, Petersdorf GR, ed. Principles of internal medicine. Tokyo: McGraw-Hill Kogakusha Ltd, 1977;1572-4. 4. Skarstein A. The diagnosis of peritonitis. Scand J Gastroenterol 1984;100:16-18. 5. Diethelm AG. The acute abdomen. In: Sabiston DC, ed. Textbook of surgery. Philadelphia, PA. W. B. Saunders Co., 1986;790-809. 6. Jenson CB, Smith GA. A clinical study of 51 cases of mesentenc infarction. Surgery 1956;40:930-7. 7 Ottinger LW, Austen WG. A study of 136 patients with mesenteric infarction. Surg GynecolObstet 1967;124:251-61. 8. Finucane PM, Arunachalam T, O'Dowd J, Pathy MSJ. Acute mesenteric infarction in elderly patients. J Am Geriatr Socl989;37:3558. 9. Marston A. Diagnosis and management of intestinal ischaemia. Ann R Coll Surg Engl 1972;50:29-44. 10. Wroblewski M. Peptic ulcer in geriatric longterm care medicine. Aging 1989;l:77-83. 11. Clinch D, Banerjee A, Ostick G. Absence of abdominal pain in elderly patients with peptic ulcer. Age Ageing 1984; 13:120-3. 12. Coleman JA, Denham MJ. Perforation of peptic ulceration in the elderly. Age Ageing 1980;9:25761. 13. Cohen MM. Treatment and mortality of perforated peptic ulcer. Can Med Assoc jf 1971;105:263-9. 14. Felix WR, Stahlgren LH. Death by undiagnosed perforated peptic ulcer. Ann Surg 1973; 177:34451. 15. Yoshikawa T. Ageing and infectious diseases. In: Pathy MSJ, ed. Principles and practice of

18.

19. 20. 21.

22.

23. 24. 25. 26.

geriatric medicine. Chichester: John Wiley & Sons. 1986;227-38. Dawson JL, Hanon I, Roxburgh RA. Diverticulitis coli complicated by diffuse peritonitis. Br J SMr#1965;52:354-7. Ekelund P, Johansson S. Polypoid cystitis. Ada Pathol Microbiol Immunol Scand 1979,87:17984. Almgren B, Bergqvist D, Hedehn H. Intraperitoneal bladder perforation caused by indwelling Foley catheter. Scand J Urol Nephrol 1977;ll:297-9. Hubbel DS, Barton WK, Solomon OD. Appendicitis in older people. Surg Gvnecol Obstet 1960;l 10:289-92. Williams JS, Hale HW. Acute appendicitis in the elderly. Ann Surg 1965;162:208-12. McCallion J, Canning GP, Knight PV, McCallion JS. Acute appendicitis in the elderly: a 5year retrospective study. Age Ageing 1987;16:256-60. Charlesworth D, Baker RH. Surgery in old age. In: Brocklehurst JC, ed. Textbook of geriatric medicine and gerontology. Edinburgh: Churchill Livingstone, 1978;712-30. Sherman ED, Robilard E. Sensitivity to pain in the aged. Can Med Assoc J 1960;83:944-7. Burdette W, Rasmussen B. Perforated peptic ulcer. Surgery 1968;63:576-85. Pathy MSJ. Clinical presentation of myocardial infarction in the elderly. Br Heart J 1967;29:190-9. Wroblewski M, Mikulowski P, Steen B. Symptoms of myocardial infarction in old age: clinical case, retrospective and prospective studies. Age Ageing 1986;15:99-104.

Authors' addresses M. Wroblewski, Department of Community Health Sciences, Lund University, Varnhem Hospital, S-21216 Malmo, Sweden P. Mikulowski, Department of Pathology, Lund University, Malmo General Hospital. Sweden Received in revised form 13 June 1990