Paedics Flashcards

Question

A number of disorders may masquerade as gastroenteritis and, when in doubt, hospital referral is essential. Name these disorders What investigations are done for dehydration or gastroenteritis How is it managed(if there’s no dehydration,if there’s dehydration,if there’s shock ) In gastroenteritis, death is from dehydration; its prevention or correction is the mainstay of management Rapid intravenous therapy is indicated in shock from gastroenteritis. However, it may be harmful in head injury, malnutrition or diabetic ketoacidosis. It was also harmful in a trial of severe febrile illness without shock in children in Africa (FEAST trial). Under these circumstances, intravenous fluids should be given cautiously and clinical response monitored closely. True or false

Answer 1

Systemic infections:Septicaemia, meningitis Local infections:Respiratory tract infection, otitis media, hepatitis A, urinary tract infection Surgical disorders:Pyloric stenosis, intussusception, acute appendicitis, necrotizing enterocolitis, Hirschsprung disease Metabolic disorders:Diabetic ketoacidosis Renal disorders:Haemolytic uraemic syndrome Others Coeliac disease, cow’s milk protein allergy, lactose intolerance, adrenal insufficiency Investigation Usually, no investigations are indicated. Stool culture is required if the child appears septic, if there is blood or mucus in the stools, or the child is immunocom- promised. It may be indicated following recent foreign travel, if the diarrhoea has not improved by day 7, or if the diagnosis is uncertain. Plasma electrolytes, urea, creatinine, and glucose should be checked if intravenous fluids are required or there are features suggestive of hypernatraemia. If antibiotics are started, a blood culture should be taken. No dehydration: Prevent dehydration Continue breastfeeding and other milk feeds Encourage fluid intake to compensate for increased gastrointestinal losses Discourage fruit juices and carbonated drinks Oral rehydration solution (ORS) as supplemental fluid if at increased risk of dehydration Dehydration: Oral rehydration solution Give fluid deficit replacement (50 ml/kg) over 4 hours as well as maintenance fluid requirement. Give ORS often and in small amounts Continue breastfeeding Consider supplementing ORS with usual fluids if inadequate intake of ORS If inadequate fluid intake or vomits persistently, consider giving ORS via nasogastric tube If there’s Deterioration or persistent vomiting, do intravenous therapy for rehydration:Replace fluid deficit over 24 hours in most cases and give maintenance fluids Unless a recent weight measurement is available, clinical estimation of hydration status is difficult. Consider fluid deficit to be 100 ml/kg (10% body weight) if shock is present and 50 ml/kg (5% body weight) if not in shock For maintenance fluids see Table 6.1 Give 0.9% sodium chloride solution or 0.9% sodium chloride solution with 5% glucose Monitor plasma electrolytes, urea, creatinine, and glucose. Consider intravenous potassium supplementation Continue breastfeeding if possible After rehydration : After rehydration Give full strength milk and reintroduce usual solid food Avoid fruit juices and carbonated drinks Advise parents – diligent hand washing, towels used by infected child not to be shared, do not return to childcare facility or school until 48 hours after last episode Shock Intravenous therapy Give bolus of 0.9% sodium chloride solution. Repeat if necessary. If remains shocked, consider consulting paediatric intensive care specialist. If signs of shock improve give IV therapy for rehydration (same as in dehydration),After this, do things after rehydration (same as in dehydration)

Answer 2

Hypernatraemic dehydration The management of hypernatraemic dehydration can be particularly difficult. Oral rehydration solution should be used to rehydrate hypernatraemic children with clinical dehydration. If intravenous fluids are required, a rapid reduction in plasma sodium concentration and osmolality will lead to a shift of water into cerebral cells and may result in seizures and cerebral oedema. The reduction in plasma sodium should therefore be slow. The fluid deficit should be replaced over at least 48 hours (with 0.9% or 0.45% saline) and the plasma sodium measured regularly, aiming to reduce it at less than 0.5 mmol/l per hour. he mechanism of action of oral rehydration solu- tion is shown in Fig. 14.11. Large quantities of sodium are excreted into the intestine, but nearly all is reab- sorbed. The primary mechanism of sodium absorption is by a glucose–sodium transporter, with the active absorption of sodium allied to the absorption of glucose. The sodium is then actively pumped from epi- thelial cells into the circulation via sodium/potassium adenosine triphosphatase, creating an electrochemical gradient that water moves down. A second mechanism is via an active, linked sodium–hydrogen exchanger. If an oral solution contains both sodium and glucose, sodium and passive water absorption is increased. This works effectively even in the presence of inflammation of the gut, and is therefore effective in diarrhoeal illness. The oral rehydration solution does not ‘stop’ the diarrhoea, which often continues, but the absorp- tion of water and solutes exceeds secretion and keeps the child hydrated until the infective organism is eradicated. Coca-Cola and apple juice have a much lower sodium content and higher osmolarity than oral rehydration solution and are unsuitable as oral rehy- dration solutions. Antidiarrhoeal drugs (e.g. loperamide, Lomotil) and antiemetics There is no place for medications for the vomiting or diarrhoea of gastroenteritis in children as they: • areineffective • mayprolongtheexcretionofbacteriainstools • canbeassociatedwithside-effects • addunnecessarilytocost • focusattentionawayfromoralrehydration. Antibiotics Antibiotics are not routinely required for gastroenteritis even if there is a bacterial cause. They are only indicated for suspected or confirmed sepsis, extra- intestinal spread of bacterial infection, for salmonella gastroenteritis if aged under 6 months, in malnourished or immunocompromised children, or for specific bac- terial or protozoal infections (e.g. Clostridium difficile associated with pseudomembranous colitis, cholera, shigellosis, giardiasis). Nutrition In developing countries, multiple episodes of diarrhoea are a major contributing factor to the development of malnutrition. Following diarrhoea, nutritional intake should be increased. Diarrhoea may be associated with zinc deficiency and supplementation may be helpful in both acute diarrhoea and as prophylaxis.

Answer 3

Postgastroenteritis syndrome Infrequently, following an episode of gastroenteritis, the introduction of a normal diet results in a return of watery diarrhoea. In such cases, oral rehydration therapy should be restarted. Gastroenteritis • Results in death from dehydration of hundreds of thousands of children worldwide every year. • Is mostly viral, but it can be caused by Campylobacter, Shigella, and Salmonella and other organisms. • Infants are particularly susceptible to dehydration. • Dehydration is assessed as no clinical dehydration, clinical dehydration or shock according to symptoms and signs, but clinical assessment of severity is problematic. • Oral rehydration solution is the mainstay of treatment and usually effective; intravenous fluid is only required for shock or ongoing vomiting or clinical deterioration. Malabsorption Disorders affecting the digestion or absorption of nutrients manifest as: • abnormalstools •poor weight gain or faltering growth in most but not all cases • specificnutrientdeficiencies,eithersinglyorin combination. The true malabsorption stool is difficult to flush down the toilet and has an odour that pervades the whole house. In general, colour is a poor guide to abnormality. Reliable dietetic assessment is important. It is inappropriate to investigate children for malabsorption as a cause of their faltering growth when dietary energy intake is demonstrably low and other symptoms are absent. Some disorders affect- ing the small intestinal mucosa or pancreas (chronic pancreatic insufficiency) may lead to the malabsorp- tion of many nutrients (pan-malabsorption), whereas others are highly specific, e.g. zinc malabsorption in acrodermatitis enteropathica

Answer 4

Coeliac disease Coeliac disease is an enteropathy in which the gliadin fraction of gluten and other related prolamines in wheat, barley, and rye provoke a damaging immu- nological response in the proximal small intestinal mucosa. As a result, the rate of migration of absorptive cells moving up the villi (enterocytes) from the crypts is massively increased but is insufficient to compensate for increased cell loss from the villous tips. Villi become progressively shorter and then absent, leaving a flat mucosa. The age at presentation is partly influenced by the age of introduction of gluten into the diet. The classical presentation is of a profound malab- sorptive syndrome at 8–24 months of age after the introduction of wheat-containing weaning foods. There is faltering growth, abdominal distension and buttock wasting, abnormal stools, and general irrita- bility.The clinical features of coeliac disease can be highly variable and include mild, non-specific gastrointestinal symptoms, anaemia (iron and/or folate deficiency) and growth faltering. Alternatively, it is identified on screening of children at increased risk (type 1 diabetes mellitus, autoimmune thyroid disease, Down syndrome) and first-degree relatives of individu- als with known coeliac disease. Diagnosis Although the diagnosis is strongly suggested by posi- tive serology, confirmation depends upon the demon- stration of mucosal changes (increased intraepithelial lymphocytes and a variable degree of villous atrophy and crypt hypertrophy) on small intestinal biopsy performed endoscopically followed by the resolu- tion of symptoms and catch-up growth upon gluten withdrawal. Although there is no place for the empirical use of a gluten-free diet as a diagnostic test for coeliac disease, strongly positive serological tests such as anti-tTG and EMA in symptomatic individuals may make the need for biopsy confirmation unnecessary in a small propor- tion of children following assessment by a paediatric gastroenterologist. Management All products containing wheat, rye, and barley are removed from the diet and this results in resolution of symptoms. Supervision by a dietician is essential. In children in whom the initial biopsy or the response to gluten withdrawal is doubtful, a gluten challenge may be required in later childhood to demonstrate continuing susceptibility of the small intestinal mucosa to damage by gluten. The gluten-free diet should be adhered to for life. Non-adherence to the diet risks the development of micronutrient deficiency, especially osteopenia, and there is a small but definite increased risk in bowel malignancy, especially small bowel lymphoma. Coeliac disease • A gluten-sensitive enteropathy. • Classical presentation is at 8–24 months of age with abnormal stools, faltering growth, abdominal distension, muscle wasting, and irritability (now rare). • Other, more subtle, modes of presentation – e.g. short stature, anaemia, abdominal pain and screening, e.g. children with diabetes mellitus, are now much more common Diagnosis – positive serology (immunoglobulin A tissue transglutaminase and endomysial antibodies), flat mucosa on duodenal biopsy (usually but not always performed), and resolution of symptoms and catch-up growth upon gluten withdrawal. • Treatment – gluten-free diet for life.

Answer 5

Short bowel syndrome usually occurs when an infant or child has had a large surgical resection. This may be due to congenital atresia, necrotizing enterocolitis, malrotation with volvulus, or a traumatic event such as a road traffic accident. Depending on the length and type of residual bowel (ileum or jejunum) and pres- ence of ileocaecal valve, these children may develop malabsorption diarrhoea and malnutrition. If severe, they may require supplemental parenteral nutrition for their intestinal failure. They are at risk from nutritional deficiencies, intestinal failure-associated liver disease, and central line-associated bloodstream infections, and need to be managed by specialist multidisciplinary teams. Cholestatic liver disease or biliary atresia: Bile salts no longer enter duodenum in the bile. This leads to defective solubilization of the products of triglyceride hydrolysis. Fat and fat-soluble malabsorption result Lymphatic leakage or obstruction: Chylomicrons (containing absorbed lipids) unable to reach thoracic duct and the systemic circulation, e.g. intestinal lymphangiectasia (abnormal lymphatics) Short bowel syndrome: Small-intestinal resection, due to congenital anomalies or necrotizing enterocolitis, leads to nutrient, water and electrolyte malabsorption Loss of terminal ileal function: e.g. resection or Crohn's disease Absent bile acid and vitamin B12 absorption Exocrine pancreatic dysfunction, e.g. cystic fibrosis Absent lipase, proteases, and amylase lead to defective digestion of triglyceride, protein, and starch (’pan-nutrient malabsorption’) Small-intestinal mucosal disease • Loss of absorptive surface area, e.g. coeliac disease • Specific enzyme defects, e.g. transient lactase deficiency following gastroenteritis, but is uncommon • Specific transport defects, e.g. glucose–galactose malabsorption (severe life- threatening diarrhoea with first milk feed), acrodermatitis enteropathica (zinc malabsorption, also erythematous rash around mouth and anus)

Answer 6

Chronic non-specific diarrhoea This condition, previously known as toddler diarrhoea, is the most common cause of persistent loose stools in preschool children. Characteristically, the stools are of varying consistency, sometimes well formed, some- times explosive and loose. The presence of undigested vegetables in the stools is common. Affected children are well and thriving. In a proportion of children the diarrhoea may result from undiagnosed coeliac disease or excessive ingestion of fruit juice, especially apple juice. Occasionally the cause is temporary cow’s milk allergy following gastroenteritis, when a trial of a cow’s milk protein free diet may be helpful. Once possible underlying causes have been excluded, in the majority of cases the loose stools probably result from dysmo- tility of the gut (a form of irritable bowel syndrome) and fast-transit diarrhoea; it almost always improves with age. Summary Chronic diarrhoea • In an infant with faltering growth, consider coeliac disease and cow’s milk protein allergy. • Following bowel resection, cholestatic liver disease or exocrine pancreatic dysfunction, consider malabsorption. • In an otherwise well toddler with undigested vegetables in the stool, consider chronic non-specific diarrhoea Inflammatory bowel disease Approximately a quarter of patients present in child- hood or adolescence, and in contrast with the adult population, Crohn’s disease is more common than ulcerative colitis. Crohn’s disease can affect any part of the gastrointestinal tract from mouth to anus, whereas in ulcerative colitis the inflammation is confined to the colon. Inflammatory bowel disease may cause poor general health, restrict growth, and have an adverse effect on psychological well-being. Management requires a specialist multidisciplinary team.

Answer 7

Crohn’s disease ``` Growth failure Puberty delayed Classical presentation (25%): • abdominal pain • diarrhoea • weight loss General ill health: • fever • lethargy • weight loss Extra-intestinal manifestations: • oral lesions or perianal skin tags • uveitis • arthralgia • erythema nodosum ``` Lethargy and general ill health without gastrointestinal symptoms can be the presenting features, particularly in older children. There may be considerable delay in diagnosis as it may be mistaken for psychological problems. It may also mimic anorexia nervosa. The presence of raised inflammatory markers (platelet count, erythrocyte sedimentation rate, and C-reactive protein), iron-deficiency anaemia, and low serum albumin are helpful in both making a diagnosis and confirming a relapse. Crohn’s disease is a transmural, focal, subacute, or chronic inflammatory disease, most commonly affecting the distal ileum and proximal colon . Initially, there are areas of acutely inflamed, thickened bowel. Subsequently, strictures of the bowel and fistulae may develop between adjacent loops of bowel, between bowel and skin or to other organs (e.g. vagina, bladder). Diagnosis is based on endoscopic and histological findings on biopsy. Upper gastrointestinal endo- scopy, ileocolonoscopy and small bowel imaging are required. The histological hallmark is the presence of non-caseating epithelioid cell granulomata, although this is not identified in up to 30% at presentation. Small bowel imaging may reveal narrowing, fissuring, mucosal irregularities and bowel wall thickening. Remission is induced with nutritional therapy, when the normal diet is replaced by whole protein modular feeds (polymeric diet) for 6–8 weeks. This is effective in 75% of cases. Systemic steroids are required if ineffective. Relapse is common and immunosuppressant medi- cation (azathioprine, mercaptopurine or methotrexate) is almost always required to maintain remission. Anti- tumour necrosis factor agents (infliximab or adalimu- mab) may be needed when conventional treatments have failed. Long-term supplemental enteral nutrition (often with overnight nasogastric or gastrostomy feeds) may be helpful in correcting growth failure. Surgery is necessary for complications of Crohn’s disease – obstruction, fistulae, abscess formation or severe localized disease unresponsive to medical treat- ment, often manifesting as growth failure. In general, the long-term prognosis for Crohn’s disease beginning in childhood is good and most patients lead normal lives, despite occasional relapsing disease. Growth failure and delayed puberty are features of Crohn’s disease in children.

Answer 8

Ulcerative colitis Ulcerative colitis is a recurrent, inflammatory and ulcerating disease involving the mucosa of the colon. Characteristically, the disease presents with rectal bleeding, diarrhoea and colicky pain. Weight loss and growth failure may occur, although this is less frequent than in Crohn’s disease. Extra-intestinal complications include erythema nodosum and arthritis. The diagnosis is made on endoscopy (upper and ileocolonoscopy) and on the histological features, after exclusion of infective causes of colitis. There is a confluent colitis extending from the rectum proximally for a variable length. In contrast to adults, in whom the colitis is usually confined to the distal colon, 90% of children have pancolitis. Histology reveals mucosal inflammation, crypt damage (cryptitis, architectural distortion, abscesses and crypt loss), and ulceration. Small bowel imaging is required to check that extra- colonic inflammation suggestive of Crohn’s disease is not present. In mild disease, aminosalicylates (e.g. mesalazine) are used for induction and maintenance therapy. Disease confined to the rectum and sigmoid colon (rare in children) may be managed with topical steroids. More aggressive or extensive disease requires systemic ster- oids for acute exacerbations and immunomodulatory therapy, e.g. azathioprine alone to maintain remission or in combination with low-dose corticosteroid therapy. There is a role for biological therapies such as infliximab or ciclosporin in patients with resistant disease, but if ineffective, surgery should not be delayed. There is an increased inci- dence of adenocarcinoma of the colon in adults (1 in 200 risk for each year of disease between 10–20 years from diagnosis). Regular colonoscopic screening is performed after 10 years from diagnosis. Hirschsprung disease The absence of ganglion cells from the myenteric and submucosal plexuses of part of the large bowel results in a narrow, contracted segment. The abnormal bowel extends from the rectum for a variable distance proximally, ending in a normally innervated, dilated colon. In 75% of cases, the lesion is confined to the rectosigmoid, but in 10% the entire colon is involved. Presentation is usually in the neonatal period with intestinal obstruction heralded by failure to pass meconium within the first 24 hours of life. Abdominal distension and later bile-stained vomiting develop (Fig. 14.16). Rectal examination may reveal a narrowed segment and withdrawal of the examining finger often releases a gush of liquid stool and flatus. Temporary improvement in the obstruction following the dilata- tion caused by the rectal examination can lead to a delay in diagnosis. Occasionally, infants present with severe, life- threatening Hirschsprung enterocolitis during the first few weeks of life. In later childhood, presentation is with chronic constipation, usually profound, and asso- ciated with abdominal distension but usually without soiling. Growth failure may also be present. Diagnosis is made by demonstrating the absence of ganglion cells, together with the presence of large, acetylcholinesterase-positive nerve trunks on a suction rectal biopsy. Anorectal manometry or barium studies may be useful in giving the surgeon an idea of the length of the aganglionic segment but are unreliable for diagnostic purposes. Management is surgical and usually involves an initial colostomy followed by anas- tomozing normally innervated bowel to the anus. Summary Hirschsprung disease • Absence of myenteric plexuses of rectum and variable distance of colon. • Presentation – usually intestinal obstruction in the newborn period following delay in passing meconium. In later childhood – profound chronic constipation, abdominal distension, and growth failure. • Diagnosis – suction rectal biopsy.

Answer 9

Constipation is an extremely common reason for consultation in children. Parents may use the term to describe decreased frequency of defecation, the degree of hardness of the stool or painful defecation. The ‘normal’ frequency of defecation is highly variable and varies with age. Infants have an average of four stools per day in the 1st week of life, but this falls to an average of two per day by 1 year of age. Breastfed infants may not pass stools for several days and be entirely healthy. After 1 year of age, most children have a daily bowel action. A pragmatic definition of constipa- tion is the infrequent passage of dry, hardened faeces often accompanied by straining or pain and bleeding associated with hard stools. There may be abdominal pain, which waxes and wanes with passage of stool or overflow soiling.The constipation may have been pre- cipitated by dehydration or reduced fluid intake or an anal fissure causing pain. In older children, it may relate to problems with toilet training, refusal and anxieties about opening bowels at school or in unfamiliar toilets. Examination usually reveals a well child whose growth is normal, the abdomen is soft and any abdominal distension is normal for age. The back and perianal area are normal in appearance and position. A soft faecal mass may sometimes be palpable in the lower abdomen, but is not necessary for the diagnosis. A primary underlying cause for constipation is rare, but a number of underlying conditions should be consid- ered: Hirschsprung disease, lower spinal cord prob- lems, anorectal abnormalities, hypothyroidism, coeliac disease and hypercalcaemia. Failure to pass meconium within 24 hours of life :Hirschsprung disease Faltering growth/growth failure :Hypothyroidism, coeliac disease, other causes Gross abdominal distension:Hirschsprung disease or other gastrointestinal dysmotility Abnormal lower limb neurology or deformity, e.g. talipes or secondary urinary incontinence :Lumbosacral pathology Sacral dimple above natal cleft, over the spine – naevus, hairy patch, central pit, or discoloured skin :Spina bifida occulta Abnormal appearance/ position/patency of anus :Abnormal anorectal anatomy Perianal bruising or multiple fissures :Sexual abuse Perianal fistulae, abscesses, or fissures : Perianal Crohn's disease Digital rectal examination should not be performed; it may sometimes be considered by a paediatric specialist to help identify anatomical abnormalities or Hirschsprung disease.

Answer 10

In more long-standing constipation, the rectum becomes overdistended, with a subsequent loss of feeling the need to defecate. Involuntary soiling may occur as contractions of the full rectum inhibit the internal sphincter, leading to overflow. The initial aim is to evacuate the overloaded rectum completely. This can generally be achieved using a disimpaction regimen of stool softeners, initially with a macrogol laxative, e.g. polyethylene glycol 3350 + electrolytes (Movicol Paediatric Plain). An escalating dose regimen is administered over 1–2 weeks or until impaction resolves. If this proves unsuccessful, a stimulant laxa- tive, e.g. senna, or sodium picosulphate, may also be required. If the polyethylene glycol + electrolytes is not tolerated, an osmotic laxative (e.g. lactulose) can be substituted. Disimpaction must be followed by maintenance treatment to ensure ongoing regular, pain-free defeca- tion. Polyethylene glycol (with or without a stimulant laxative) is generally the treatment of choice. The dose should be gradually reduced over a period of months in response to improvement in stool consistency and frequency. The addition of extra fibre to the diet is not helpful, and may make stools larger and more difficult to pass. The child should be encour- aged to sit on the toilet after mealtimes to utilize the physiological gastrocolic reflex and improve the likeli- hood of success. The outcome is more likely to be successful if the child is engaged in the treatment process. This requires exploring the child’s concerns and motivation to change. Sometimes use of behavioural interven- tions, e.g. a star chart, is helpful to record and reward progress, as well as to motivate the child. Encouragement by family and health professionals is essential, as relapse is common and psychological support is sometimes required. The mainstay of treat- ment is the early, aggressive and prolonged use of laxative medication in a dose that allows the passage of a large, soft stool at least once a day. One needs to emphasise that the use of laxatives is safe, even long-term, as underuse is the commonest reason for treatment failure. Occasionally, the faecal retention is so severe that evacuation is only possible using enemas or by manual evacuation under an anaesthetic. They should only be performed under specialist supervision, paying particular attention to avoiding distress and embarrassment for the child.

Answer 11

Features of genital disorders in children are: • hydroceles,inguinalherniasandundescended testes usually arise from abnormal embryological development • theacutescrotumisasurgicalemergency • foreskinconditionsandhypospadiasarecommon in boys • vulvovaginitis and labial adhesions are common in girls. Inguinoscrotal conditions Embryology Development of a testis from an early indeterminate gonad is determined by genes associated with a Y chro- mosome. For a testis to descend from its origin on the posterior abdominal wall, it must produce testosterone which acts on peripheral tissues. The testis, guided by the mesenchymal gubernaculum, migrates down into the inguinal canal .The structures that are found in the scrotum in a boy (testis, vas and blood vessels) or labium in a girl (attachment of the round ligament of the uterus) pass through the abdominal wall and pick up layers corresponding to those of the abdominal wall. In a boy these make up the cover- ings of the spermatic cord. In boys and girls there is a remnant of peritoneal invagination, the processus vaginalis (Fig. 20.1b), which, if it remains patent and in continuity with the abdomen, explains why fluid or abdominal contents can become a hydrocele or hernia, respectively Varicocele This is a scrotal swelling comprising dilated (varicose) testicular veins and occurs in up to 15% of boys, usually at puberty (Fig. 20.4). Its cause is multifactorial; valvular incompetence plays a role. It is commoner on the left side because of drainage of the gonadal vein into the left renal vein, which also receives blood containing catecholamines from the left adrenal vein. It is usually asymptomatic, but may cause a dull ache. On examina- tion it may have a bluish colour and feel like a ‘bag of worms’. Sometimes the testis is smaller or softer than normal. Management is conservative if asymptomatic. Occlusion of the gonadal veins can be achieved by surgical ligation – through the groin laparoscopically or by radiological embolization.

Answer 12

Inguinal hernia Inguinal hernias are common, occurring in up to 5% of boys, and are even more common in premature babies. As explained by the embryology, a hernia is usually caused by a persistently patent processus vaginalis and emerges from the deep inguinal ring through the inguinal canal. It is therefore usually indirect, although in premature babies where the tissues are weak and friable, direct hernias are more likely than in older children. A hernia presents as a lump in the groin which may extend into the scrotum or labium. They are usually asymptomatic but may be intermittent, visible during straining. On examination, sometimes a lump or thickened cord structures can be palpated in the groin. The contents of the hernia may become irreducible (incarcerated), causing pain and sometimes intestinal obstruction or damage to the testis (strangulation). In these circumstances the lump is tender and the infant may be irritable and may vomit. The risk of incarcera- tion is much higher in infants than in older children. Most hernias can be successfully reduced by ‘taxis’ (gentle compression in the line of the inguinal canal) with good analgesia. Surgery can then be planned for a suitable time when any oedema has settled and the child is well. If reduction is impossible, emergency surgery is required because of the risk of compromise of the bowel or testis. In girls, sometimes the ovary can become incarcerated within a hernia. Surgery involves ligation and divi- sion of the processus vaginalis, which has become the hernial sac (herniotomy, removal of the hernia sac – as opposed to herniorrhaphy in adults, when the inguinal abdominal wall is also reinforced, usually with a mesh). Beyond the first three months of age, this can be safely performed as a day case. Prompt surgical repair is indicated for inguinal hernias in infants to lower the risk of incarceration Hydrocele A hydrocele has the same underlying anatomy as a hernia, but the processus vaginalis, although patent, is not sufficiently wide to form an inguinal hernia. Hydroceles are usually asymptomatic and some- times appear blue. It is usually possible to feel the testis, however tense the hydrocele. Sometimes the hydrocele is separate from the testis in the cord. The key to differentiating a hernia from a hydrocele is the ability to ‘get above’ a hydrocele. Hydroceles usually transilluminate (Fig. 20.3). Although the processus vaginalis is often patent at birth it usually closes within months. Hydroceles therefore usually resolve spontaneously, and can be managed expectantly. Surgery may be considered if it persists beyond the first two years of life, but resolu- tion may take longer than this.

Answer 13

Undescended testis .Unde- scended testes are present in up to 5% of newborn term infants but are more common in premature infants. By three months of age, only 1% are still unde- scended. The diagnosis should ideally be made at the routine examination of the newborn but since there is still a small spontaneous rate of descent after this time the decision to operate for undescended testis should be delayed. Examination of the testes in babies must be made in a warm environment and with warm hands. The testes may be felt in the scrotum or may need to be delivered by gentle pressure along the line of the inguinal canal to the scrotum. An undescended testis may be palpable or impal- pable. A palpable undescended testis is usually seen or felt in the groin, but cannot be manipulated into the scrotum. Occasionally it can be palpated below the external inguinal ring but outside the scrotum – the so-called ‘ectopic’ testis. If the testis is impalpable, it may be in the inguinal canal but cannot be identified or it may be intra- abdominal or absent. If there are bilateral impalpable testes, the karyotype must be established to exclude disorders of sex development. This should be regarded as a medical emergency. A testis may also be retractile. The crucial difference between a retractile and undescended testis is that a retractile testis can be manipulated into the scrotum with ease and without tension. Action of the cremaster muscle (as seen in eliciting the cremasteric reflex by light touch on the abdominal wall) pulls up the testis. Parents of boys with a retractile testis often report that the testis is sometimes obvious, particularly when the boy is warm and relaxed, and sometimes not.

Answer 14

Investigations and management Imaging is not helpful in the assessment of an un- descended testis. Orchidopexy, the surgical placement of the testis in the scrotum, is performed for the following reasons: • Cosmetic–toachievethesame,symmetrical appearance as other boys. This may be of psychological benefit. If the testis is absent, a prosthesis can be inserted when older. • Reducedriskoftorsionandtraumacomparedto groin location • Fertility–thetestisneedstobeinthescrotum, below body temperature, in order to allow spermatogenesis. The effect is probably marginal in unilateral undescended testis but is more important if bilateral. There is some evidence that delaying orchidopexy beyond the first two years of life adversely affects testicular development. • Malignancy–increasedriskinanundescended testis, which is greater if bilateral or intra- abdominal. Placing the testis in the scrotum facilitates self-examination but may not influence the risk of malignancy. The timing of orchidopexy depends on local surgical and anaesthetic facilities, but should be per- formed before or around one year of age. Groin approach orchidopexy involves opening the inguinal canal in a similar manner to herniotomy, mobi- lizing the testis whilst preserving the vas and blood vessels and placing it within the scrotum. It is usually performed as a day case. An intra-abdominal testis is usually managed laparoscopically; it may be amenable to placement in the scrotum in a single operation or may require a staged approach. For a retractile testis, follow up is recommended because some high testes require surgery to place them in the scrotum. Whether or not this is true ascent of the testis is controversial. Acute inguinoscrotal conditions (‘the acute scrotum’) Torsion of the testis This is commonest in post-pubertal boys but may occur at any age, including the newborn when it usually presents at birth and is believed to be perinatal. It is usually very painful, with redness and oedema of the scrotal skin. However, the pain may be localised to the groin or lower abdomen, highlighting the need to always examine the testes in a boy present- ing with sudden-onset pain in the groin, abdomen or scrotum. It must be distinguished from an incarcerated hernia. An undescended testis is at increased risk of torsion, as is a testis lying transversely on its attach- ment to the spermatic cord (the so-called ‘clapper bell’ testis). Torsion of the testis must be treated within hours of the onset of symptoms to lower the risk of testicular 370 loss. In fact, surgical exploration in any acute scrotal presentation is mandatory unless torsion can be excluded with certainty (see below). Fixation of the contralateral testis is essential because of the increased risk of a contralateral torsion, especially if an anatomical abnormality is present in the torted testis. Outcome is variable, depending on time to correction. If delayed, testicular loss is likely. In perinatal testicular torsion, testicular loss is almost inevitable.

Answer 15

Torsion of appendix testis A testicular appendage (Hydatid of Morgagni) is a Mul- lerian (paramesonephric) remnant usually located on the upper pole of the testis. Torsion of the appendix testis (Fig. 20.5b) tends to affect prepubertal boys and is more common than torsion of the testis. Pain evolves over days, but is not as dramatic as in testicular torsion. Scrotal exploration and excision of the appendage is often necessary because it cannot be differentiated reliably from torsion of the testis. If a ‘blue dot’ can be seen through the scrotal skin and pain is controlled with analgesia, surgery may not be necessary. Other acute inguinoscrotal conditions Infection may cause an acute scrotum. Epididymo- orchitis is commoner in infants and small children, and more likely with a pre-existing urological or anorectal malformation. As it may be indistinguish- able from torsion, scrotal exploration may be necessary. Doppler ultrasound of flow pattern in the testicular blood vessels may allow differentiation of epididymitis from torsion of the testis, but must not delay surgical exploration if torsion remains a possibility. A urine sample should be obtained to identify an associated urinary tract infection. Pus should be sent at operation for microbiology to characterize the nature of the infec- tion, but infection may be bacterial or viral. Antibiotics are started empirically. In idiopathic scrotal oedema there is redness and swelling extending beyond the scrotum into the thigh, perineum and suprapubic area, but the testis is normal and non-tender. It requires analgesia and review. It may recur. An incarcerated hernia may also cause an acute scrotum, although symptoms usually affect the groin. Trauma to the scrotum is an uncommon cause of testicular damage, but may need exploration, debride- ment and surgical repair. Sexual abuse needs to be considered in all genital injuries. Recurrent scrotal pain in boys can be difficult to manage. Any associated symptoms or signs such as swelling or redness should be regarded as intermittent testicular torsion and the testes fixed.

Answer 16

Abnormalities of the penis The foreskin A normal foreskin does not retract in infancy, and retraction should not be attempted. The prepuce develops adherent to the underlying glans, and acts as protection to the non-keratinised glanular and meatal squamous epithelium in an environment where astringent urine can cause inflammation or even ulceration. This can be manifest as ammoniacal dermatitis (napkin rash) in infants and young children, where the preputial opening can be reddened and sore. It usually only needs reassur- ance and attention to routine hygiene. This needs to be differentiated from infection, or balanoposthitis, where the redness is more extensive, and, crucially, there is a purulent discharge. The infection is usually bacterial and needs antibiotic treatment, either topical or systemic. As it is rarely fungal, antifungal agents are not indicated. Topical corticosteroids may sometimes be beneficial. Ballooning of the foreskin on urination is a common cause of parental concern. It can look dramatic but seldom causes any trouble. It results from lysis of preputial adhesions around the glans before those at the preputial opening. Ballooning may also occur on the shaft of the penis, arising from the attachment of shaft skin below the coronal sulcus of the glans. Bal- looning stops when preputial adhesions have lysed completely. It has no functional consequence, does not represent obstruction, and does not need intervention. Another cause of parental concern is sub-preputial smegma. It appears as a lump which grows briefly, seemingly under the non-retractile or partially retrac- tile foreskin. It is yellowish and malleable, and simply comprises desquamated skin and secretions. There is no need to intervene – it will discharge in due course (with typical appearance of smegma – ‘cottage cheese’; when the preputial adhesions break down. Paraphimosis This is a condition, usually in post-pubertal boys, of a retracted foreskin that cannot be reduced easily. There is a ring of narrower skin. The glans swells, and if the prepuce is not reduced it may result in compromise of the blood supply to the glans. Treat- ment (by reduction) is an emergency, which may require general anaesthesia. Paraphimosis has been regarded as an indication for circumcision, but this is no longer considered to be the case unless the foreskin is abnormal (as with BXO). Non-retractile foreskin and phimosis When traction is applied (gently) to a normal foreskin, the skin at the preputial opening is seen to evert, even if it does not necessarily open up .A foreskin that is pathologically non-retractile will not do this, and will truly render the glans ‘muzzled’, (Greek word ‘phimos’). This differentiates a foreskin that is simply non-retractile (i.e. normal, physiological) from one which is problematic. The commonest condition that gives rise to a true phimosis is balanitis xerotica oblit- erans, or BXO, which gives rise to progressive scarring which can extend onto the glans, into the meatus and ultimately into the urethra. Typically this affects older boys and young adults, and there is often a history that the foreskin was normally retractile in earlier child- hood. Figure 20.9 shows the typical appearance of BXO. BXO is the index indication for circumcision, although there is some evidence that potent topical steroids, closely monitored, can cause it to regress.

Answer 17

Circumcision Circumcision remains a tradition in Jewish and Muslim religions. Medical reasons for circumcision include: • BXO causing a true phimosis • recurrent balanoposthitis causing refractory symptoms • prophylaxis of recurrent urinary infection, especially in the presence of a congenital uropathy (such as posterior urethral valves or vesicoureteric reflux) or if renal reserve is limited • ifaccesstotheurethraisrequiredreliablyfor intermittent catheterization, e.g. spina bifida. There are inevitably other indications for circum- cision, some of which are highly dependent on the individual family and surgeon. There is some evidence that circumcision affords protection against transmis- sion of HIV and HPV (human papillomavirus), and there are programmes promoting circumcision in newborn infants and young adult males in some countries with high prevalence of HIV infection. There have been many techniques described for circumcision, and complications are uncommon. Up to one boy in fifty has post-operative bleeding requiring a return to the operating theatre. Infection in the skin margin or ulceration of exposed granular skin may occur. Meatal stenosis can also occur, more often after circumcisions done for BXO, and this may require sub- sequent surgery. Rarer complications include urethral fistula. A non-retractile foreskin is normal in preschool children Hypospadias . It is thought to arise from failure of development of ventral tissues of the penis – in particular failure of ventral urethral closure. For that reason it is really a constellation of ‘ventral hypoplasia’ of the penis. Typically there are three features, although their occurrence is variable: • a ventral urethral meatus–theurethralmeatusis variable in position but in most (80%) is on the distal shaft or glans penis (Fig. 20.11a) • ventralcurvatureoftheshaftofthepenis(formerly called ‘chordee’) (Fig. 20.11b), more apparent on erection • hoodedappearanceoftheforeskin–characteristic in appearance because of ventral foreskin deficiency but of no functional significance. Management Surgery is not mandatory, especially in a distal hypospadias when the penis and urinary stream are straight. However, it may be performed on functional or cosmetic grounds. The ultimate functional aim of hypospadias surgery is to allow a boy to pass urine in a straight line whilst standing, and to have a straight erection. Surgery, if needed, is usually performed in the first two to three years of life. The commonest surgical complications are breakdown of the repair or meatal narrowing. The prepuce may be preserved and recon- structed, although for more proximal hypospadias it is sometimes required for the repair itself. For this reason it is important that a boy with hypospadias is not circumcised before the repair.

Answer 18

Other conditions of the penis Variations in penoscrotal skin attachment and in the infant or child’s body habitus may make the penis look buried. This is common with obesity, when the only treatment is weight loss, but improves with growth of the penis after puberty. However, it may persist if there is marked obesity. Summary Genital conditions in male infants Inguinal hernia/hydrocele • Cause inguinoscrotal swellings: clinically one can get above a hydrocele • Expedient surgical repair of inguinal hernias is required in infants to prevent bowel strangulation or after reduction of an irreducible hernia Undescended testis • Common – up to 5% of term boys • If testis palpable, requires orchidopexy • If impalpable, may require laparoscopy to establish presence of a testis • If bilateral impalpable, urgent karyotype is essential • Retractile testes usually do not require surgery Acute scrotal conditions • May occur at any age but torsion of testis must be considered not only for acute pain of the scrotum but also for acute abdominal and groin pain • scrotal surgical exploration is required unless torsion of the testis can be reliably excluded Non-retractile foreskin • Is normal in preschool children • Is pathological if associated with BXO • Circumcision is not recommended routinely but is still traditional in some communities worldwide Hypospadias • Common – 1 in 200 boys • Variable ventral urethral meatus and penile curvature • Surgery may be required in first two years of life • Infants with hypospadias must not be circumcised

Answer 19

Genital disorders in girls Vulvovaginitis/vaginal discharge The commonest problem is redness of the vulva. In infants, this is often due to a nappy rash due to ammoniacal dermatitis. Less often, the vulvovaginitis is infective, occasionally with Candida infection. Vaginal discharge is common, and is usually innocuous unless it is green or offensive when it may indicate infec- tion. Foreign bodies are more often suspected than found; they are actually rare. The ‘red flag’ symptom is a bloody vaginal discharge, and needs referral to a specialist as vaginal rhabdomyosarcoma is a rare but important cause in preschool girls. Labial adhesions Fusion of the labia minora can be a cause of local irrita- tion in the prepubertal girl. There is usually an adequate orifice for the passage of urine. The characteristic appearance is of superficial fusion of the labia minora with a translucent (or even slightly bluish) area of flimsy tissue between the labia. Topical corticosteroids or oestrogens can be helpful to lyse the adhesions, especially if it allows the underlying introital anatomy to be seen, but readhesion is common. Other conditions True obstruction or atresia of the vagina is rare. It may present with primary amenorrhoea in adolescence. This might co-exist with cyclical abdominal or pelvic pain representing obstruction to the flow of menses. Clinical examination usually reveals the cause. If there is a bulging introitus that appears blue, the diagnosis is imperforate hymen – and the treatment is hyme- notomy under anaesthesia. Absence of an imperforate hymen represents a problem of vaginal septation, canalization or more complex abnormality with para- mesonephric (Mullerian) duct development, and needs further imaging (often with MRI) to plan appropriate management. An ovarian cause for symptoms should be considered in a girl who presents with acute abdominal pain (from ovarian cyst or torsion) or a mass (cyst or tumour). Blood-stained vaginal discharge must be investigated Summary Genital conditions in female infants • Vulvovaginitis in infants is usually due to nappy rash •

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