About a New Palpation Sign in the Diagnosis of Acute Appendicitis in Children and Women of Childbearing Age

Abstract

Acute appendicitis (AA) is defined as nonspecific bacterial inflammation of the appendix vermiformis and is the most common acute abdominal condition requiring surgical intervention. The clinical picture of atypical forms of AA (children, women of childbearing age) is often insidious with its unpredictable onset and course. The diagnosis is particularly problematic. The new palpation sign consists of two reflex arcs. The visceral reflex arc ensures the diagnosis of an early stage of acute appendicitis, on the other hand, the somatic reflex arc points to the late stage of acute appendicitis. Due to the technical simplicity of the new palpation sign and the positioning of the patient during the examination, it is effective in a restless and distrustful child, as well as in women of childbearing age in differentiating AA from a gynecological disease.

1. Introduction

Almost 140 years after its first description by Fitz (1886), acute appendicitis (AA) remains an insidious, unpredictable, and dangerous disease, which causes diagnostic difficulties with its unpredictable onset and course. The diagnosis of atypical forms of AA is particularly problematic, especially in children and women of childbearing age.

Overall, 1–8% of children presenting with abdominal pain have AA [1]. In young children (newborns and infants), appendicitis is an uncommon event with a varied presentation and complications that can develop rapidly [1]. The incidence of acute appendicitis gradually increases after birth, peaks during the late teens, and gradually declines in the geriatric age. A Danish study reported an annual incidence of 2.22/10,000 among boys under 4 years of age and 1.82/10,000 among girls under 4 years of age. The annual incidence among 10–19-year-old boys and girls was 22/10,000 and 18/10,000, respectively [2]. The rate of incorrect diagnosis concerning AA ranges from 28% to 57% in 2–12-year-old children, and is almost 100% in children under 2 years of age [3]. The risk of AA perforation decreases with the child’s age as follows: 100% < 1 year; 100% 1–2 years; 83.3% 2–3 years; 71.4% 3–4 years; 78.6% 4–5 years, and 47.3% 5 years [4]. The reason is delayed diagnosis of the disease in young children.

Early diagnosis of AA in children is therefore a challenge for the physicians.

In women of childbearing age, the anatomical proximity of the appendix vermiformis to the internal genitalia causes frequent diagnostic confusion of AA with gynecological diseases (e.g., an ectopic pregnancy, pelvic inflammatory disease, midcycle pain occurring with ovulation, endometriosis, ovarian torsion) [5, 6]. AA is more common in men than in women (3:2) [7]. Despite this statistical data, the risk of a lifelong acute appendectomy in women is higher than in men (2:1), which can be explained by the more difficult diagnosis of AA in women, with a higher number of preventive appendectomies with negative histological findings [7].

In this chapter, we present scientific and medical societies a new palpation sign as a reliable tool for the diagnosis of atypical forms of AA (i.e., in children and women of childbearing age) and an effective indicator for surgical intervention.

2. New palpation sign

The new palpation sign (described by Vitezslav Marek in 2020) belongs to the group of viscerosomatic palpation signs. Its benefit lies in the diagnosis of AA in patients at risk, such as children and women of childbearing age.

2.1 Description of the new palpation sign

“We place the patient on his/her left side with their knees bent. In children, we palpate the abdomen with our right hand. The thumb is located in the lumbar region and pushes into the abdominal cavity. Using 2–4 fingers, the surgeon pushes the abdominal wall of the right hypogastrium into the abdominal cavity. If we notice pulsation of the iliac artery, the sign is considered negative, i.e., this sign excludes AA. If a deep palpation induces a contracture of the abdominal wall (abdominal guarding) which does not allow the pulsation of the iliac arteries to be felt, even when the child is exhaling, the sign is considered positive, i.e., there is a high probability of acute appendicitis (Figure 1)” [8, 9].

Figure 1.

(a) Examination of a child younger than 3 years of age. Position of the “pietá di Michelangelo” (authors archive). (b) Examination of a child older than 3 years of age (authors archive).

“We examine the abdomen of a woman of childbearing age bimanually. The thumbs press on the lumbar region, pushing it into the abdominal cavity. Using the fingers of both hands, the surgeon pushes the abdominal wall of the right hypogastrium into the abdominal cavity. With pulsation of the iliac artery during palpation, the sign is considered negative, i.e., it excludes AA. Attention should be paid to examining the internal genitalia of the woman. If deep palpation induces a contracture of the abdominal wall (abdominal guarding) that does not allow the pulsation of the iliac artery to be felt, the sign is considered positive, i.e., there is high probability of acute appendicitis (Figure 2)” [8, 9].

Figure 2.

Examination of a woman of childbearing age (authors archive).

2.2 Clinical anatomy of the new palpation sign

Neurological basis of the palpation sign is a combination of a somatomotor and visceromotor segmental reflex mediated by the intercostal nerves (Th6–Th12). Reflexes are activated through deep palpation of the abdominal wall of the right hypogastrium, which touches and compresses the inflamed appendix vermiformis [8].

The somatomotor reflex is induced by pressing the inflamed parietal peritoneum of the abdominal wall of a patient with an inflamed appendix. The nerve impulse is transmitted from the receptors of the parietal peritoneum of the abdominal wall through the afferent fibers of the cerebrospinal nerve pathway to the spinal ganglion cells in the posterior roots of the spinal cord, where they are connected to the alpha motor neuron via an interneuron. The alpha motor neuron originates from the anterior spinal roots, innervates the abdominal muscles, and activates the abdominal guarding [8].

Visceromotor reflex is formed by compression of the inflamed appendix through the abdominal wall, no peritonitis is required. The nerve impulse transmits from receptors located in the appendix wall (the Pacinian bodies and the free nerve endings) through the afferent splanchnic nerve pathway to the posterior roots of the spinal cord. The close anatomical location of afferent splanchnic, cerebrospinal fibers, and the alpha motor neuron causes the intense signal created by compression of the inflamed appendix to induce a “spillover” phenomenon with direct activation of the alpha motor neuron, causing abdominal guarding (Figure 3) [8].

Figure 3.

(a) Somatomotor reflex. (b) Visceromotor reflex. 1, Afferent fibers of the pseudo unipolar cell; 2, posterior spinal roots; 3, interneuron; 4, alpha motor neuron; 5, associated ascending pathways (into the brain); 6, associated ascending pathways (into the brain) [10].

Activation of the somatomotor and visceromotor reflex results in spasm of the abdominal muscles—“abdominal guarding”—preventing deeper abdominal palpation and palpation of the iliac artery pulsations [8].

3. Clinical presentation and diagnosis of AA

3.1 Children

In early childhood, the diagnosis of AA is difficult and in most cases delayed. This delay is caused by its nonspecific clinical manifestation, which is often covered up by other nonspecific childhood diseases, as well as the child’s inability to describe and specify their own health problems.

Newborns (birth to 30 days) with AA usually present with abdominal distension in 60% to 90%, vomiting 59%, palpable mass 20–40%, irritability or lethargy in 22%, cellulitis of abdominal wall in 12–16%, hypotension, hypothermia, and respiratory distress [11]. AA is rare in this age group. This is explainable by the so-called fetal appendix shape (orificium of the appendix to the caecum is wide) with a low tendency to obstruction of the lumen and subsequent formation of AA.

AA in newborns progresses rapidly due to:

• a small omentum majus—unable to limit inflammation in the right hypogastrium,

• low plasticity of the peritoneum—the inability to isolate and limit inflammation,

• low resistance of the child’s organism to infection.

Infants and toddlers (less than 3 years) with AA usually do not respond to caressing and are not satisfied in their mother’s arms. In most cases, a caring mother only suspects that the child has a stomach ache, but cannot explain it exactly. In such cases, the recommendation of Professor Tosovsky applies: “We must never underestimate and contradict mother’s opinion, thinking that our professional knowledge entitles us to do so. It is the quickest way to a mistake” [12]. Maternal instinct is important in diagnosing AA in this age group. It is questionable whether mothers who prioritize career and personal life over child care have developed this maternal bond.

The prominent symptoms in this age group are vomiting (85–90%), pain (35–81%), fever (40–60%), diarrhea (18–46%), cough or rhinitis (40%), grunting respiration (8–23%), right hip mobility restriction, pain, and limping in 3–23% [13].

Preschool (age 3–5 years). Even in this age group, the incidence of AA is rare and accounts for less than 5% of all childhood appendicitis [1]. With growing age, children are able to communicate well and can describe the symptoms of acute appendicitis, early diagnosis of acute appendicitis becomes more easy and accurate. Abdominal pain dominates in AA in pre-school children (89–100%). This is followed by vomiting (66–100%), fever (80–87%), and anorexia (53–60%) [1].

3.1.1 Clinical examination

During the clinical examination of the abdomen, each patient is approached individually.

The nature of the child, the level of dissimulation is assessed through calm and repeated examinations. When palpating the abdomen, the overall reactions of the child are evaluated—facial redness, involuntary movements of the limbs, and

Macenko’s interesting observation: “…when palpating in the right hypogastrium, the child pulls the right lower limb and pulls the examiner’s hand away” [14].

The effort is to identify palpable pain in the right hypogastrium and the presence of peritoneal irritation, which represents a “sign over sign.” A certain degree of experience is necessary to distinguish the protective muscle tension of the abdominal wall (abdominal guarding in peritonitis) from the free contraction of the abdominal wall in children due to their fear. The new palpation sign eliminates this disadvantage. Its essence is the palpation of the pulsation of the iliac artery, not the subjective assessment of pain and reflex tension of the abdominal muscles. Palpation of the pulsation of the iliac arteries is an objective indicator that is not affected by the restlessness of the child.

3.1.2 Ultrasonography (US)

Using US for the acute appendicitis diagnosis is convenient and safe, but its effectiveness is highly operator dependent. Basic ultrasound findings indicating acute appendicitis are: swollen appendix (diameter > 6 mm), an appendicolith, high echogenicity surrounding the appendix (caused by inflammation), pericecal free fluid, and thickened bowel loops with weakened peristalsis [15, 16]. The analysis by Yasmine Lounis et al. found that the sensitivity for first abdominal US diagnosing AA in children was 65.5%. In most of children in whom abdominal ultrasound was false negative, appendix was either not or incompletely visualized [17].

3.1.3 Computed tomography (CT), magnetic resonance imaging (MRI)

CT has been considered the radiological gold standard to confirm clinical and US suspicion of appendicitis with high sensitivity and specificity (72–99% and 84%) [18]. Among the basic diagnostic signs in a CT examination of a child with AA are:

swollen appendix (diameter more than 6 mm), focal apical thickening of the appendix, lymphadenopathy, presence of an appendicolith and abscesses [16]. Repeated CT carries a proven risk of increased cancer incidence in children, and its use should therefore be limited to clear indications with a well-defined risk-benefit ratio [19]. Advantages of CT include less operator dependence, easier visualization of the retrocecal appendix, and less intestinal gas interference.

A Finnish study demonstrated comparable diagnostic accuracy of contrast-enhanced low- dose CT and standard CT in the diagnosis of AA, with the mean radiation dose of low-dose CT significantly reduced (3.33 vs. 4.44 mSv) [20].

Magnetic resonance imaging (MRI) is a feasible alternative to CT for secondary imaging in AA in children and can reliably distinguish perforated from non-perforated AA [21].

3.1.4 Biochemical and hematological markers

Various biochemical and hematological markers have been established for improving the diagnostic accuracy of acute appendicitis in younger children (Table 1). Below the common ones are discussed:

In blood/serum	In urine
White blood cell count (WBC)	Urine 5-hydroxyindoleacetic acid (5-HIAA)
Differential leukocyte counts (DLC	Urine leucine-rich alpha glycoprotein-2 (LRG)
C-reactive proteins (CRP)
Erythrocyte sedimentation reaction (ESR)
Tumor necrosis factor alpha (TNF-alpha), acid)
Alpha1-glycoprotein (alpha1gp)
Leucocyte elastase complex (elastase)
Interleukin-8 (IL-8)
Interleukin-6 (IL-6)
Interleukin-10 ( IL-10)
Granulocyte colony stimulating factor
Interferon gamma
Soluble intercellular adhesion molecule-1
Matrix metalloproteinase-9
Tissue inhibitor metalloproteinase-1
Serum amyloid A
Plasma calprotectin
Plasma serotonin
Serum leucine-rich alpha glycoprotein-2 (LRG)
Procalcitonin

Table 1.

The most common biological markers used in the diagnosis of appendicitis [22].

3.1.5 Complete blood count (CBC) and CRP

Although the white blood cell (WBC) count is increased in acute appendicitis, still it is nonspecific and insensitive. Furthermore, the WBC count cannot differentiate between a complicated and an uncomplicated acute appendicitis.

C-reactive protein (CRP) is a nonspecific inflammatory mediator. It has a sensitivity of 43–92% and a specificity of 33–95% for diagnosing acute appendicitis in children presenting with abdominal pain [23]. The sensitivity of leukocytosis and increased neutrophil count may approach 98% with an elevated CRP for diagnosing acute appendicitis [24].

3.1.6 Neutrophils-to-lymphocytes (NLR) ratio

The neutrophil-to-lymphocyte ratio (NLR) is a simple, inexpensive, and reliable parameter of systemic inflammation. The NLR is derived from a differential of white blood cells when the number of circulating neutrophils is divided by the number of circulating lymphocytes. Kahramanca et al. reported NLR limit values of 4.68 (65% sensitivity, 55% specificity) for the diagnostics of acute appendicitis and NLR ≥ 5.74 (71% sensitivity, 49% specificity) for distinguishing between complicated and uncomplicated appendicitis [25]. Shashirekha et al. reported NLR limit values of 3.0 (81% sensitivity, 53% specificity) and 5.5 (78.4% sensitivity, 41.7% specificity) for the diagnostics of AA and perforated appendicitis, respectively [26].

A combination of clinical examination (with new palpation sign), laboratory tests, and US may significantly improve diagnostic sensitivity and specificity.

3.1.7 Algorithm for diagnosis and treatment of children with suspected AA

Acute appendectomy is indicated in children with suspected AA with positive clinical examination (new palpation sign) and a positive US, without the needs of a CT scan or MRI. If the clinical examination (new palpation sign) is negative, if US is suspected, conservative treatment (antibiotic therapy) with patient observation (repeated clinical and US examination every 6 hours) is recommended. MRI or diagnostic +/− therapeutic laparoscopy is indicated for failure of conservative treatment (Figure 4) [9].

Figure 4.

Algorithm for diagnosis and treatment of children with suspected AA (authors archive).

Several studies on this topic have shown no difference in the rate of postoperative complications between children who underwent appendectomy after failure of conservative (antibiotic) treatment and children who were treated surgically at the first presentation of AA [27, 28].

3.2 Women of childbearing age

The course of AA in a woman of childbearing age can be confusing and still presents a diagnostic problem, in which it is necessary to distinguish between gynecological and non-gynecological diseases (Table 2).

Lower quadrant abdominal pain in young women
Non-gynaecological disease	Gynaecological disease
Appendicitis	Ectopic pregnancy
Crohn’s disease	Ruptured follicular or corpus luteum cyst
Meckel’s diverticulitis	Ovarian torsion
Sigmoid diverticulitis	PID
Perforated peptic ulcer	Haemorhage of an ovarian cyst
Viral gastroenteritis	Mittelschmera
Mesenteric adenitis	Endometriosis
Ventral and inguinal hernias
Urological disease:
Pyelonephritis
Perinephric abscess
Urolithiasis
Urinary tract infections

Table 2.

Differential diagnosis of diseases causing pain in the right hypogastrium in women of childbearing age.

AA and pelvic inflammatory disease (PID) are two of the most common causes of abdominal pain in women of childbearing age [6]. PID encompasses a spectrum of diseases that include salpingitis, endometritis, and tuboovarian sepsis.

As with AA, the diagnosis of PID is extremely important because more than 60% of women who experience severe PID or multiple episodes of PID become infertile. In addition, missed or delayed diagnosis is associated with chronic pelvic pain and ectopic pregnancy [29].

The first symptom differentiating AA from PID is the duration of abdominal pain. The pain of acute appendicitis usually lasts 24–36 hours, while the pain of PID can last for weeks or until it is treated and is characterized by no worsening.

A study by Morishita et al. from 2007 is currently the most relevant in terms of the clinical picture of these two pathologies. In this retrospective study, data from 181 women with abdominal pain, 109 with a diagnosis of appendicitis, and 72 with PID were analyzed. Women with PID were younger, with bilateral pelvic pain and fever. Conversely, women with acute appendicitis initially had periumbilical pain migrating to the right iliac fossa, loss of appetite, nausea, and vomiting [30].

3.2.1 Clinical examination

During the clinical examination of the abdomen in a woman of childbearing age, the position of the patient at the new palpation sign is used to distinguish AA from PID. Its principle lies in the different degree of fixation of the appendix and internal genitalia in the female abdominal cavity. When positioning the patient with PID on the left side, the maximum palpable pain shifts from the Mc Burney point toward the left hypogastrium, the pulsation of the iliac artery is palpated. On the contrary, in AA, the pain remains fixed at McBurney’s point, palpation causes contracture of the abdominal wall and does not allow to feel the pulsation of the iliac arteries.

A complete clinical examination must always include a gynecological examination with a smear from the cervix to detect possible infections and a transvaginal US. In addition, an adequate sexual history should always be investigated (e.g., the presence of an intrauterine device that can cause PID).

3.2.2 Ultrasonography (US)

Among radiological examinations, US is certainly the first diagnostic step in young women of childbearing age with acute abdominal pain. Its sensitivity and specificity are relatively low, because both clinical diagnoses (AA, PID) have similar US sings. Among the US signs defining acute appendicitis can be included: non-compressible, aperistaltic tubular structure with a blind end with a diameter greater than 6 mm, echogenic periappendicular fat (due to inflammation) and hyperemia in the thickened wall of the appendix identified by color Doppler ultrasound [31]. Abdominal ultrasound in the diagnosis of acute appendicitis has a sensitivity of 75–90% and a specificity of 85–98% [16]. In case of an ambiguous diagnosis, transvaginal US is indicated, which enables more accurate visualization of the adnexa and uterus.

3.2.3 Computed tomography (CT), magnetic resonance imaging (MRI)

When the clinical presentation is nonspecific and the ultrasound is non-diagnostic, patients undergo abdominopelvic computer tomography (CT) with contrast medium [30].

Hentour’s criteria (appendiceal diameter and left tubal thickening) are used for CT differential diagnosis of AA and PID.

When interpreting an abdominopelvic CT in women of childbearing age with suspected AA, the following procedure is recommended:

1. Measurement of the diameter of the appendix

2. Measurement of the thickness of the left Fallopian tube.

If the diameter of the appendix is < 7 mm and the thickness of the left Fallopian tube ≥ 10 mm, appendicitis is improbable, PID highly probable. If the diameter of the appendix is ≥ 7 mm and the thickness of the Fallopian tube does not reach 10 mm, the diagnosis of AA is confirmed [32]. The most common direct CT signs of PID include:

haziness of the pelvic fat, obscuration of the pelvic fascial planes, thickening of the uterosacral ligaments, abnormal endometrial enhancement with fluid in the endometrial cavity, enhancement and thickening of the fallopian tubes, and enlarged, reactively altered polycystic ovaries [33].

The sensitivity of CT in appendicitis is from 87% to 98%, higher than US [30].

Magnetic resonance plays a secondary role due to its financial complexity. Its advantage is the absence of radiation exposure and excellent specificity and sensitivity in the diagnosis of acute appendicitis or PID. However, it should be reserved for specific population groups (pregnant women, children) [34]. MRI has sensitivity and specificity for diagnosis of appendicitis of 95% and 89%, respectively.

3.2.4 Biochemical and hematological markers

Routine laboratory tests for the diagnosis of AA in women of childbearing age include:

• Complete blood count, leukocyte count, CRP and NLR. These are nonspecific indicators of inflammation with low differential diagnostic specificity between AA and PID.

• Physical and chemical examination of urine is indicated for the exclusion of urological diseases—kidney or bladder stones (hematuria) or inflammatory diseases of the urinary tract (pyuria, bacteriuria).

• Biochemical examination of blood with a focus on hepatic tests and serum amylases is helpful in differentiating diseases of the hepatobiliary tract and pancreas from AA.

• Examination of human chorionic gonadotropin test (b-hcg) to exclude an unrecognized or ectopic pregnancy [35].

Second-level laboratory tests may be useful in patients with nonspecific abdominal symptoms. Among them, cervical smear to diagnose genital infections (such as Neisseria gonorrhea or Chlamydia trachomatis) is certainly important, which would support the diagnosis of PID [34]. Rapid tests for the detection of these microorganisms are available. The findings of 10 or more polymorphonuclear (PMN) leukocytes on a gram-stained endocervical smear are diagnostic of mucopurulent cervicitis and may also help confirm the diagnosis of PID [36].

3.2.5 Algorithm for diagnosis and treatment of women of childbearing age with suspected AA

Laparoscopic appendectomy is indicated in women of childbearing age with suspected AA with positive clinical examination (new palpable sign), high suspicion on US, and negative gynecological examination. If the clinical examination (new palpation symptom) is negative, with high US suspicion, diagnostic +/− therapeutic laparoscopy is recommended (Figure 5).

Figure 5.

Algorithm for diagnosis and treatment of women of childbearing age with suspected AA (authors archive).

4. Conclusion

Despite the intensive technological development of imaging examinations, the medical history and clinical examination of the abdomen in AA remains a basic diagnostic tool.

We introduced a new palpable sign and described its clinical anatomy consisting of two reflex arcs. The visceral reflex arc ensures the diagnosis of the early stage of acute appendicitis. It is activated by compression of the inflamed appendix, no peritonitis is required. Conversely, the somatic reflex arc is activated when the peritoneum is affected by inflammation and indicates the late stage of acute appendicitis.

The examination itself using the new palpation sign is not technically demanding. It can be performed even with a restless and distrustful child. In women of childbearing age, the very position of the patient with a new palpation sign makes it possible to distinguish between gynecological and non-gynecological diseases.

The new palpation sign serves as a reliable indicator for surgery, minimizes unindicated revisions of the abdominal cavity, and is suitable for diagnosing AA in atypical forms (i.e., in children and women of childbearing age) with a sensitivity of 95.57% and a specificity of 95.78% [9].

Due to its material and technical simplicity, it can be used in various parts of the world and in emergency situations where diagnostic equipment and technologies are limited. It represents a first-line diagnostic tool, but also a suitable part of a scoring diagnostic system.

The combination of expertise, experience, and humility of the surgeon turns the diagnosis of AA into a surgical art.

Acknowledgments

This chapter is dedicated to the children who perished during senseless wars caused by human hatred.