EUH Morning Report: What are the diagnostic accuracy of the Kernig and Brudzinski sings for diagnosing adult meningitis? Part 2

The Bottom Line: “In the broad spectrum of adults with suspected meningitis, 3 classic meningeal signs did not have diagnostic value; better bedside diagnostic signs are needed.” (Thomas)

See Part 1 on the Kernig and Brudzinski signs: https://emorymedicine.wordpress.com/2024/03/14/euh-morning-report-what-are-the-sensitivity-and-specificity-of-the-kernig-and-brudzinski-sings-for-diagnosing-adult-meningitis/

Thomas et. al’s prospective study found that “the 3 classic meningeal signs—Kernig’s sign, Brudzinski’s sign, and nuchal rigidity—were of limited clinical diagnostic value for adults with suspected meningitis. None of these meningeal signs were able to accurately discriminate patients with meningitis (⩾6 WBCs/mL of CSF) from those without it. Furthermore, no significant correlation existed between these meningeal signs and moderate meningeal inflammation (⩾100 WBCs/mL of CSF) or between these meningeal signs and microbiological evidence of CSF infection. Only for the 4 patients with severe meningeal inflammation (⩾1000 WBCs/mL of CSF) did nuchal rigidity have 100% sensitivity, 100% negative predictive value, and LR+ : LR- that approached infinity.” (Thomas)

“The sensitivity of both Kernig’s sign and Brudzinski’s sign was 5%, which suggests that these bedside diagnostic tools did not reliably identify the need for lumbar puncture among patients with meningitis. Although the specificity of both signs was 95%, the high specificity values were a result of the overall paucity of positive results of examination for Kernig’s sign and Brudzinski’s sign, rather than a reflection of the discriminating ability of these indicators. The positive and negative predictive values for Kernig’s sign (27% and 72%, respectively), Brudzinski’s sign (27% and 72%, respectively), and nuchal rigidity (26% and 73%, respectively) also indicate that none of the classic meningeal signs were clinically discriminating indicators of the presence or absence of meningitis” (Thomas)

(Thomas)

EUH Morning Report: What are the sensitivity and specificity of the Kernig and Brudzinski sings for diagnosing adult meningitis? Part 1

The Bottom Line: “Since the overall accuracy of JAH and other clinical signs [of meningitis] is in poor to fair range, they do not have good performance alone in detection of meningitis. It seems that physicians should not solely rely on a single test or sign, and they should consider a collection of clinical signs and symptoms and history to have a better judgment. A lot of retrospective and prospective studies have shown that diagnosis of meningitis should be made according to the results of physical examination, history and CSF analysis.” (Ala)

In their 2018 prospective study, Ala et al. found that “that diagnostic value of JAH in diagnosis of meningitis in emergency department is higher than other clinical signs such as Kernig, Brudzinski and neck stiffness but the accuracy of all the mentioned signs is in poor to fair range (AUC 60 to 80). JAH had the highest sensitivity (84.4%) and Kernig and Brudzinski had the highest specificity (89.3% and 90.6%, respectively) among the evaluated signs.” (Ala)

(Ala)

This is congruent with the finds of prospective studies by Nakao et al. (2014) and Mofidi et al. (2017), that the Kernig and Brudzinski signs have low sensitivity but high specificity. And that along with Jolt Accentuation, the absence of the clinical signs of meningitis cannot rule out the diagnosis of meningitis.

“Although poorly sensitive, the physical examination findings of Kernig sign, Brudzinski sign, nuchal rigidity, vomiting, and rash were all relatively specific for both pleocytosis and moderate pleocytosis; however, because sensitivity was low for all of these features, LRs suggest that these findings are ultimately unhelpful. For the finding of moderate pleocytosis, however, high specificity resulted in potentially useful, although not diagnostic, LRs for a positive finding of jolt accentuation, Kernig sign, and Brudzinski sign.” (Nakao)

However, the “combination of Jolt accentuation, Kernig’s sign, and Brudzinski’s sign has 100% specificity and PPV and a very high LR+, so we can suppose a high possibility of meningitis for a patient with headache and fever and a positive result of all of 3 tests.” (Mofidi)

(Mofidi)

Ala, Alireza et al. “Accuracy of Neck stiffness, Kernig, Brudzinski, and Jolt Accentuation of Headache Signs in Early Detection of Meningitis.” Emergency (Tehran, Iran) vol. 6,1 (2018): e8. Free Full Text.

Nakao, Jolene H et al. “Jolt accentuation of headache and other clinical signs: poor predictors of meningitis in adults.” The American journal of emergency medicine vol. 32,1 (2014): 24-8. Full Text at Emory.

Mofidi, Mani et al. “Jolt accentuation and its value as a sign in diagnosis of meningitis in patients with fever and headache.” Turkish journal of emergency medicine vol. 17,1 29-31. 24 Nov. 2016. Free Full Text.

Midtown Morning Report: What is the differential diagnosis for aseptic meningitis?

The Bottom Line: “The signs and symptoms of aseptic meningitis are often vague and nonspecific; therefore, the differential is quite broad. The headache and fever, being some of the most common symptoms, drive the differential.
Bacterial meningitis is the most concerning and common alternative cause and should be the default diagnosis until ruled out. Intracranial hemorrhage, especially subarachnoid hemorrhage, should be considered in patients with the appropriate clinical presentation. Neoplastic disorders (leukemia, tumors of the brain), other types of headaches (migraine), inflammation of brain structures (brain abscess, epidural abscess) should also be considered.
Fever from almost any source can present with headache and neck stiffness as associated symptoms. Urinary tract infections and pneumonia can present with headaches, body aches, and fever. Thus, an exhaustive search for infectious sources is part of every workup.
Many of the causes of aseptic meningitis may give most or all of the symptoms but have no meningeal involvement. Viral syndromes, in particular, often give headaches, muscle aches, weakness, and fever.

EUH Morning Report: How accurate are the Kernig and Brudzinski signs in diagnosing meningitis?

The Bottom Line: 

Brudzinski and Kernig signs of meningeal irritation appear unreliable for diagnosis or ruling out of meningitis.

EUH Morning Report: What is hypertrophic pachymeningitis?

The Bottom Line:  “Hypertrophic pachymeningitis (HP) is a rare inflammatory disorder characterized by marked fibrous thickening of the cerebral and/or spinal dura matter.”

Figure 2. Contrast-enhanced axial T1WI demonstrates diffuse pachymeningeal enhancement.