Acute appendicitis
BMJ 2006; 333 doi: https://doi.org/10.1136/bmj.38940.664363.AE (Published 07 September 2006) Cite this as: BMJ 2006;333:530All rapid responses
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Dear Sir,
We note with interest the different perforation rates in appendicitis
between children and adults.[1] We agree that this complication of
appendicitis does account for the majority of morbidity and mortality. The
figure quoted in the article for children was up to 97%; however we are
somewhat concerned that this may be misleading as the primary data used to
support this figure is based on the Murphy (1904) personal experience and
largely is of historical interest rather than of current relevance.[2] The
second reference (Bickell 2006) is a retrospective review of 219 cases of
proven appendicitis with a median age of 29.3 years.[3] We are concerned
that this will lead practitioners into a falsely pessimistic view of
outcomes in young children and could potentially provide justification for
poor standards of care.
Our current outcome data for children aged 0-15 years at Sheffield
Children’s Hospital gives a perforation rate of 23.8% (May 2004-May 2006,
n=273) defined on the basis of final pathology report. Looking at the
subgroup of under 5 year olds, which paediatric surgeons and
paediatricians commonly view as the highest risk (because of the non-
specific presentation in these young children and the progression to
perforation more quickly) our perforation rate is 58.3%, (n=72) over the
last 7 years.
A complete literature review of primary research papers on paediatric
appendicitis with stated perforation rates in the last 10 years leaves 10
papers. The mean overall perforation rate was 31.1% (range 19-52%). 3
papers specifically quoted data on young children with perforation rates
being 41.9% (age2-5)[4], 82% (age 0-4) and 39% (age 0-5)[6].
Management of paediatric appendicitis is largely centred outside of
tertiary paediatric surgical units and there appears to be a need to
establish current perforation rates and set standards in management of
this common paediatric surgical emergency.
References
1. Humes DJ, Simpson J. Acute appendicitis. BMJ 2006;333:530–4.
2. Murphy J. Two thousand operations for appendicitis, with
deductions from his personal experience. Am J Med Sci 1904;128:187-211.
3. Bickell NA, Aufses JAH, Rojas M, Bodian C. How time affects the
risk of rupture in appendicitis. J Am Coll Surg 2006;202:401-6.
4. Nwomeh BC. Chisolm DJ. Caniano DA. Kelleher KJ. Racial and
socioeconomic disparity in perforated appendicitis among children: where
is the problem? Pediatrics 2006;117(3):870-5.
5. Hazebroek FW. The impact of diagnostic delay on the course of
acute appendicitis. Archives of Disease in Childhood 2000;83(1):64-6.
6. Paajanen H. Somppi E. Early childhood appendicitis is still a
difficult diagnosis. Acta Paediatrica. 1996;85(4):459-62.
Competing interests:
None declared
Competing interests: No competing interests
I believe the authors have missed one important caveat in dealing
with patients over the age of 60 years who present with acute
appendicitis.A small group of these patients will prove to have an
underlying adenocarcinoma of the caecum impinging on the base ofthe
appendix, or, more rarely, a primary adenocarcinoma of the base of the
appendix itself.It is therefore important for the surgeon to bear this
possibility in mind when palpating the appendix and caecum at operation.
Competing interests:
None declared
Competing interests: No competing interests
We have read the clinical review “Acute Appendicitis” published by
BMJ1 and we would like to share our experiences on this field with you.
Cienfuegos is a province located to the southern central region of the
island (Cuba) with a population of about 400 000 inhabitants. The primary health
assistance is well structured and there is a general university hospital
of 640 beds where adult patients received medical care.
In a four year
period (2002-2005) 2488 patients had been admitted with a diagnosis of
acute appendicitis, this being the most frequent pathology found for an
acute surgical abdomen. 61.2% of the patients were in the 15-35 age
group; out of them 69.1% were males. 49.9% patients presented with
Murphy’s sequence (abdominal pain, vomiting and fever) and 95.5% of the
cases were considered as non- complicated acute appendicitis 2.
Laparoscopy
was used as a diagnostic test with a high degree of specificity (97%), a
reason for considering it an affordable choice for developing countries.
Four periods of time were set in order to know and reduce the lasting time
between the symptoms onset and the surgical intervention: symptoms onset
- arrival to the Emergency Service - clinical diagnosis – diagnostic
confirmation - surgical intervention start. All cases were operated on in
the six hour period followed hospital arrival, and 73.3% were performed on
in the three earlier hour period.
Following the Clinical Practice Guide
recommendations 3, three doses of one gram of Cefazoline was used as
prophylactic antibiotic in 89.4% of the patients while other antibiotics
were used in the rest. 54 patients (2.17%) suffered from infection in
the surgical site and six were intervened again (0.24%) due to
complications such as: abscesses in the right iliac fossa, (2), dehiscence
of the appendicular stump (1), and diffuse peritonitis. Only four patients
who have been assessed as high surgical risk cases died (0.16%) since they
have been diagnosed complicated acute appendicitis and had other
comorbilities too.
In the year 2005, the anatopathological study of 792
surgical pieces of appendicectomized patients revealed the presence of
acute appendicitis with periappendicitis (93.6%), perforated acute
appendicitis with peritonitis (4 ,9%), and adenocarcinoma of the appendix
(0,04%). Only 1.5% of the appendixes microscopically examined were normal.
For all these reasons we concluded that acute appendicitis patients are
efficiently assisted in our hospital and this entity must be considered a
target of the surgical emergency service in hospitals.
References.
1.Humes DJ, Simpson J. Acute appendicitis. BMJ 2006;333: 530-4.
2.Soto-López A, Águila-Melero O, Reyes-Corcho A, Consuegra-Díaz JE, Gómez-
Baute R. Eficiencia diagnóstica en la apendicitis aguda. Hospital
Provincial Clínico Quirúrgico Ginecoobstétrico Docente Universitario,
Cienfuegos, Cuba. Cir Cir 2003;71(3):204-9.
3.Aguila-Melero O, Olivera-Fajardo D. Apendicitis aguda.
www.gal.sld.cu/GBP/Cirugia/Cirugía_General/Apendictis_Aguda.html
Competing interests:
None declared
Competing interests: No competing interests
EDITOR- We read with interest the clinical review of acute
appendicitis by Humes DJ and Simpson J (1). We were pleased to notice that
the authors stated that there is “no good evidence … to support the notion
that analgesia should be withheld on the ground that it may cloud the
clinical picture”. We were, however, surprised that so little stress (only
one sentence) was given to this long-dated and debated belief.
Unfortunately not only it is a belief but a practice which is still very
common, especially among children. As one of many examples, a study
published in 2006 and conducted in a large Canadian Children Hospital
showed that only 50% of children presenting to the emergency room with
suspected appendicitis received a minor pain killer (i.e. paracetamol),
while only 15% received an opioid(2).
Over the past few years the belief of withholding analgesia has been
challenged. Several controlled trials, the majority of which performed on
adults, fewer in children, consistently showed that early analgesia does
not interfere with diagnostic accuracy(3-5).
In our opinion, pain management and relief in acute abdominal pain
deserves more attention. Not only randomised controlled trial are
warranted in order to better establish dosages, time of administration,
and type of analgesic drugs to be used, but also – as importantly –
studies to monitor that “evidence” is effectively applied in the clinical
practice.
1. Humes DJ, Simpson J. Acute appendicitis. BMJ 2006;333;530-534.
2. Goldman RD, Crum D, Bromberg R, Rogovik A, Langer JC. Analgesia
administration for acute abdominal pain in the Pediatric Emergency
Department. Pediatr Emerg Care 2006;1:18-21.
3. Thomas SH, Silen W. Effect on diagnostic efficiency of analgesia
for undifferentiated abdominal pain. Br J Surg 2003;90:5-9.
4. Green R, Bulloch B, Kabani A, Hancock BJ, Tenenbein M. Early
analgesia for children with acute abdominal pain. Pediatrics 2005;116:978-
983.
5. Kokki H, Lintula H, Vanamo K, Heiskanen M, Eskelinen M. Oxycodone
vs placebo in children with undifferentiated abdominal pain. Arch Pediatr
Adolesc Med 2005;159:320-325.
Jenny Bua, resident in paediatrics,
Federico Marchetti, clinical paediatrician
Department of Paediatrics, Institute of Child Health, IRCCS Burlo
Garofolo, Trieste
Via dell'Istria 65/1, 34100 Trieste, Italy
Corresponding author:
Federico Marchetti, MD (marchetti@burlo.trieste.it)
Competing interests:
None declared
Competing interests: No competing interests
I enjoyed Humes and Simpson’s Review of this still important
topic.(1) Over 40 years ago, I studied the clinical pathology of the
appendix and the epidemiology of appendiciectomy. I would like to
comment on four complementary issues.
First, around 1960 the 4:1000 death rate ranged from 1:2600 for
uncomplicated appendicitis in young adults, to 1:9 for those over 50 with
a perforated appendix. Death rates for males were double those for
females. Deaths from a normal appendicectomy were 1:5000 in young
adults.(2) In my own study of 1412 appendicectomies, surgeons differed
over whether to risk removing normal appendices or leave abnormal ones
in, and deaths from higher and lower operative approaches balanced almost
exactly. However morbidity from the more conservative approach was
higher due to more re-admissions , and more patients continued to complain
of RIF pain.(3)
Second, 37 of 45 patients with ‘recurrent /chronic’ appendicits had
iron deposits in their appendices, a histological finding that correlated
with recent RIF pain.(4) In 119 patients with mesenteric adenitis, cure
by surgery was also likely for those whose appendices were iron-positive.
Is the concept of neuroimmune appendicitis a helpful addition to an
already idiosyncratic diagnostic area?
Third, I found no evidence that appendicitis ran in families, but
appendicectomy did. Another indication that appendicectomy was a decision
sometimes influenced by non-biomedical factors was that surgeons of all
operative approachs were more likely to remove appendices from nurses and
from colleagues’ children . (5)
Fourth, in 65 of 870 certified deaths from appendicitis, there was no
evidence of either appendicitis or an appendicectomy. In 88 of my own
series of appendicectomies, discharge classifications of appendicitis
were entered despite no histological evidence of appendicitis.
Studies of the epidemiology of appendicitis or appendicectomy need an
accurate ‘biomedical science’ diagnostic basis, and their interpretation
needs to allow for the ‘behavioural science’ components of decision making
which include doctors’ and patients’ anxieties and beliefs, and the
context of individual situations.
Two decades later, I found that the same issues applied to the use of
antibiotics by general practitioners. Whether in surgery or in general
practice, any theoretical model for clinical practice must allow for the
interaction of both biomedical and behavioural science. The challenge to
clinical practice of modern EBM and clinical guidelines is to find out how
to celebrate and incorporate the right balance between these two
interdependent sciences to counter increasingly discontinuous and target-
centred care.
References
1 Humes DJ, Simpson J. Acute appendicitis. BMJ 2006; 333:530-4. (9th
September.)
2 Howie JGR. Death from appendicitis and appendicectomy. Lancet
1966;ii:1344-7.
3 Howie JGR. The place of appendicectomy in the treatment of young
adult patients with possible appendicitis. Lancet 1968:i:1365-7.
4 Howie JGR. The Prussian-blue reaction in the diagnosis of previous
appendicitis. J Path and Bact 1966;91:85-92.
5 Howie JGR. Appendicectomy and family history. BMJ 1979;ii:1003.
Competing interests:
None declared
Competing interests: No competing interests
Editor –
We read the article by Humes and Simpson [1] with interest, however
there are a few issues arising from this article that we feel should be
highlighted that are relevant to general practitioners, and patients
alike:
It is important to clinically assess the right groin and hip,
particularly in paediatric patients as transient synovitis or irritable
hip and septic arthritis are common [2] and are differential diagnoses
that must be considered for atypical presentations. Children are often
referred with abdominal pain where the gait of the patient has not been
assessed and a painful limp can often be missed in a patient examined only
in the supine position.
Radiological investigations for appendicitis have progressed and CT
may be used in the UK in adults, particularly to rule out right sided
colonic pathologies such as cancers and diverticular disease, however for
children where radiation exposure is certainly more of an issue,
advocating CT scans on the basis of higher diagnostic precision has
potential risks to the children in question. As so much of the diagnosis
of acute appendicitis is clinical judgement, admission and repeated
examination is an important diagnostic tool that is often undervalued, now
that more sophisticated imaging is available, but still should not be
ignored.
Longer term complications of open appendicectomy includes bowel
obstruction secondary to adhesions. A recent long term follow up study [3]
demonstrated that patients who underwent appendicectomy subsequently had a
relatively low overall direct risk of readmission (0.9%). However, this
procedure accounted for approximately 30% of all abdominal procedures and
7% of all patient readmissions during the 5 years following lower
abdominal surgery, for the study in question. Appendicectomy therefore may
contribute significantly to the overall burden of adhesion-related
readmissions. The healthcare cost of adhesion related readmission is huge
– in 1994 this amounted to $1.4 billion (currently approximately £0.7
billon). [4] This potential burden of readmission from open appendicectomy
may be reduced with the use of laparoscopic surgery.
A recent meta-analysis [5] that included 11 randomized trials and
over 6000 paediatric patients demonstrated that wound infection was
significantly reduced with laparoscopic versus open appendectomy (1.5%
versus 5%; odds ratio 0.45, 95% confidence interval 0.27– 0.75), as was
ileus (1.3% versus 2.8%; odds ratio 0.5, 95% confidence interval
0.29–0.86), both of which could further reduce the readmission rates and
cost of complications subsequent to the treatment of appendicitis.
As appendicitis is such a common cause of presentation to hospital,
patients and practitioners alike should be aware of the important factors
with regards to balancing the risks of investigations and surgery
alongside the benefits of clinical judgment and new minimally invasive
therapies.
References:
1. Humes DJ, Simpson J. Acute appendicitis. BMJ. 2006 Sep
9;333(7567):530-4.
2. Fischer SU, Beattie TF. The limping child: epidemiology,
assessment and outcome. J Bone Joint Surg Br. 1999;81(6):1029-1034.
3. Parker MC, Wilson MS, Menzies D, Sunderland G, Clark DN, Knight
AD, Crowe AM; Surgical and Clinical Adhesions Research (SCAR) Group. The
SCAR-3 study: 5-year adhesion-related readmission risk following lower
abdominal surgical procedures. Colorectal Dis. 2005 Nov;7(6):551-8.
4. Ray NF, Denton WG, Thamer M, et al. Abdominal adhesiolysis:
inpatient care and expenditures in the United States in 1994. J Am Coll
Surg 1998;186:1-9.
5. Aziz O, Athanasiou T, Tekkis PP, Purkayastha S, Haddow J,
Malinovski V, Paraskeva P, Darzi A. Laparoscopic versus open appendectomy
in children: a meta-analysis. Ann Surg. 2006 Jan;243(1):17-27.
Competing interests:
None declared
Competing interests: No competing interests
Humes and Simpson rightly point out in their clinical review of acute
appendicitis that complications can occur after removal of a normal
appendix (1). In an attempt to decrease the rate of negative
appendicectomies the use of diagnostic laparoscopy followed by either
laparoscopic or open appendicectomy may be beneficial. Diagnostic
laparoscopy allows one to leave a normal looking appendix, identify
alternative pathologies or accurately site a small incision for open
appendicectomy. While working at a district general hospital where
diagnostic laparoscopy is routinely performed we audited 187 diagnostic
laparoscopies for suspected acute appendicitis over a two year period and
found 141 diagnostic laparoscopies (75%) proceeded to laparoscopic
appendicectomy while the remaining 46 patients (25%) had a macroscopically
normal appendix and no appendicectomy was performed. Hospital stay and
complications following laparoscopic appendicectomy were favourable
compared to open appendicectomy and outcomes were similar regardless of
grade of operating surgeon. Controversy persists over the safety of
leaving a “normal” looking appendix as it may be inflamed in up to 10% of
cases although the clinical significance of this is uncertain (2) despite
evidence that it is safe (3).
The European Association of Endoscopic Surgeons recommends the use of
diagnostic laparoscopy combined with laparoscopic appendicectomy for the
management of suspected acute appendicitis (4). The problem that out-of -
hours laparoscopic appendicectomy presents in many UK district general
hospitals is availability of expertise and a camera holder making open
appendicectomy the only option. With growing evidence supporting routine
use of diagnostic laparoscopy we feel that combined with laparoscopic
appendicectomy it should be an integral part of surgical training. Our
experience suggests that this is both safe and feasible. With growing
public awareness patients may soon demand that they be given a choice.
Faheez Mohamed, Specialist Registrar General Surgery,Northern
Deanery. E-mail: faheez@btinternet.com
Kevin Khoo, Surgical Research Fellow, Wansbeck General Hospital,
Ashington.
References
1. Humes DJ, Simpson J.Acute appendicitis. BMJ 2006;333:530-4.
2. Barrat C, Catheline JM, Rizk N, Champault GG. Does laparoscopy
reduce the incidence of unnecessary appendicectomies? Surg Laparosc Endosc
1999 Jan;9(1):27-31.
3. The SH, O’Ceallaigh S, McKeon JG, O’Donohoe MK, Tanner WA, Keane
FB. Should an appendix that looks “normal” be removed at diagnostic
laparoscopy for acute right iliac fossa pain? Eur J Surg 2000 May
166(5):388-9
4. Sauerland S, Agresta F, Bergamaschi R, Borzellino G, Budzynski A,
Champault G et al. Laparoscopy for abdominal emergencies: evidence-based
guidelines of the European Association for Endoscopic Surgery.
Surg Endosc. 2006 Jan;20(1):14-29.
Competing interests:
None declared
Competing interests: No competing interests
We follow the following prototocol in our unit for the last twenty
years,and in our experience it is safe.
Patient should earn appendicectomy after conservative management of
appendix mass. Surgery is indicated only if there are recurrent symptoms.
This measure will reduce the morbidity and cost of care associated with
routine interval appendicectomy.
Conservative management includes:
1. Nil by mouth
2. Antibiotics, e.g. metronidazole 500mg/8h i.v. and cefuroxime 750mg/8h
i.v.
3. The size of the mass should be marked out and surgery is indicated if
either:
o the mass enlarges or
o small bowel obstruction supervenes due to adhesions or
o the patient becomes more toxic, e.g. increased pulse, increased WCC,
increased pain, increased temperature
It is usual to do a delayed appendicectomy 6-8 weeks later, even if the
mass resolves on conservative treatment. However, about 15-20% of patients
will be readmitted with similar symptoms before the 'interval
appendicectomy'.
Note that it is important to exclude a colonic carcinoma in those beyond
middle age when symptoms settle. Barium enema or colonoscopy are first-
line investigations.
Competing interests:
None declared
Competing interests: No competing interests
In their clinical review of acute appendicitis, Humes and Simpson1
indicated that initial management of the appendix mass is initiation of
appropriate resuscitation and intravenous antibiotics and that most of the
cases will resolve. This conservative regimen for patients presenting with
appendix mass has been recently challenged by early laparoscopic surgery
which has proven to be feasible and safe.2 This also has the added
advantage of avoiding delays in diagnosing other hidden pathologies
masquerading as appendix mass such as caecal carcinoma, ileo-caecal
tuberculosis and Crohn's disease.3 Furthermore, this emergency approach
obviates the need for another hospital admission for interval
appendicectomy some 8 weeks later. In a prospective nonrandomized study,
it has been shown that early surgical intervention to be more beneficial
over the conservative approach in a cohort of 82 patients especially in
term of hospital stay which was significantly shorter in the emergency
group (4.8 vs. 13.2 days; p<_0.05.4 this="this" argument="argument" was="was" based="based" on="on" occurrence="occurrence" at="at" a="a" mean="mean" of="of" _4.3="_4.3" weeks="weeks" recurrent="recurrent" symptoms="symptoms" in="in" _19="_19" patients="patients" _39.6="_39.6" the="the" conservative="conservative" group.="group." furthermore="furthermore" periappendiceal="periappendiceal" abscesses="abscesses" and="and" adhesions="adhesions" were="were" found="found" _38="_38" _79="_79" _39="_39" _81.3="_81.3" interval="interval" appendicectomy="appendicectomy" respectively="respectively" compared="compared" to="to" _100="_100" those="those" who="who" underwent="underwent" emergency="emergency" surgery.4="surgery.4" p="p"/> The authors also mentioned that the management after resolution of
the appendix mass is interval appendiectomy.1 Recent evidence suggests
after exclusion of the presence of other hidden pathologies especially in
the elderly, interval appendicectomy is unjustified except in cases with
recurrent symptoms. A recent prospective randomized controlled trial
showed that patient treated conservatively without interval appendicectomy
had the shortest hospital stay and duration of work-days lost. Furthermore
only 10% of patients developed recurrent appendicitis during a median
follow-up period of more than 33 months.5 This evidence argues strongly
against interval appendicectomy. However, a survey of 663 surgeons in
North America revealed that interval appendicectomy is routinely performed
by 86% of the surveyed surgeons.6 The most cited reason is the risk of
recurrent appendicitis which occurs in only 20% of cases and is greatest
during the first 2 years.3,7 Hence, more than 80% of patients can be
spared the morbidity of a surgical intervention.
A recent large retrospective population-based cohort study of 1012
patients treated initially conservatively showed that only 39 patients
(5%) developed recurrent symptoms after a median follow-up of 4 years. It
was therefore concluded that interval appendicectomy after initial
successful conservative treatment is not justified and should be
abandoned.8
Based on the above evidence, it can be concluded that emergency
laparoscopic appendicectomy for appendix mass is safe and feasible and
should be considered as an option in the management of appendix mass. If
conservative treatment is instituted, there may be no need for future
interval appendicectomy. Interval appendicectomy is of questionable
benefit and may indeed be unjustified; therefore it should be reserved for
patients with recurrent symptoms after resolution of the inflammatory
mass.
Dr. Abdul-Wahed Meshikhes, FRCS
Consultant Surgeon, Department of Surgical Specialties,
King Fahad Specialist Hospital, Dammam, Eastern Province, Saudi Arabia
meshikhes@doctor.com
References
1. Humes DJ, Simpson J. Acute appendicitis. BMJ 2006;333:530–4.
2. Senapathi PS, Bhattacharya D, Ammori BJ. Early laparoscopic
appendectomy for appendicular mass. Surg Endosc 2002;16:1783-5.
3. Hoffmann J, Lindhard A, Jensen HE. Appendix mass: conservative
management without interval appendectomy. Am J Surg.1984;148:379-82.
4. Samuel M, Hosie G, Holmes K. Prospective evaluation of nonsurgical
versus surgical management of appendiceal mass. J Pediatr Surg.2002;
37:882-6.
5. Kumar S, Jain S. Treatment of appendiceal mass: prospective randomized
clinical trail. Indian J Gastroenterol 2004;23(5):165-7.
6. Chen C, Botelho C, Cooper A, Hibberd P, Parsons S. Current practice
patterns in the treatment of perforated appendicitis in children. J Am
Coll Surg. 2003;196:212-221.
7. Eriksson S, Granstrom L. Randomized controlled trial of appendectomy
versus antibiotic therapy for acute appendicitis. BrJ Surg 1995;82:166–9.
8. Kaminsk Ai,Liu I-LA, Applebaum H, Lee L, Haigh PI. Routine interval
appendectomy is not justified after initial nonoperative treatment of
acute appendicitis. Arch Surg. 2005;140:897-901.
Competing interests:
None declared
Competing interests: No competing interests
Re: Acute appendicitis
The author says that diagnosis of appendicitis is a clinical one (1). No specific diagnostic test for appendicitis exists, but the judicious use of simple urine and blood tests, particularly inflammatory response variables, should allow exclusion of other pathologies and provide additional evidence to support a clinical diagnosis of appendicitis (box 2). (1) Scoring systems and algorithms have been proposed to aid the diagnosis of acute appendicitis but have not been widely used.1 Radiological tests can be used to aid the diagnosis of acute appendicitis.1
Here we may add that measuring the severity of appendicitis is important for its further management.
According to a study published in 2016 (2):
CRP and D-dimer levels are positively correlated with the severity of acute appendicitis in children. Combined CRP and D-dimer are identified as suitable diagnostic markers for differentiating between simple and other severe appendicitis, which will provide important guidance for clinicians to determine the follow-up management of acute appendicitis2.
References:
1. BMJ 2006;333:530
2. Bu X, Chen J, Wan Y, Xu L. Diagnostic Value of D-Dimer Combined with WBC Count, Neutrophil Percentage and CRP in Differentiating Between Simple and. Clin Lab. 2016 Sep 1;62(9):1675-1681. doi: 10.7754/Clin.Lab.2016.160122.
Competing interests: No competing interests